Tell me if this sounds familiar: You've got many simultaneous projects with competing deadlines. Your contributions are needed and in each case it will cause a big problem if you fail to fulfill your obligations. So you work long hours. You don't hand off tasks to others, ask for deadline extensions, or drop the ball. You don't have much free time. You definitely don't have time to get sick. Luckily, you're healthy, and sickness isn't something you worry about.

That was me, about six weeks ago, but then the unexpected happened: I got pneumonia. The bad cough that became bronchitis in my husband quickly moved over to me and shot my temperature up to 102. I rarely get fevers, and never high ones, so I realized I had to get myself to the doctor. I also realized, no matter how badly I thought I was needed, I couldn't work. I couldn't even stay awake for more than an hour at a time.

My whole conception of how vital it was for me to complete my various jobs--on deadline--came crashing down. It was a great lesson, and one I'm grateful to have learned with a relatively minor ailment, one that was quickly cured with antibiotics and lots of rest. Before I get really sick, I'm going to try to remember to keep these things in mind:

1. Even if you're healthy, you can make yourself sick by working too hard.

Late last year, I learned to my surprise that it's actually possible to work yourself to death. Of course I know (don't we all?) that sitting too long at an office desk and too much stress can, over the years, give you things like heart disease. I suppose I knew in theory that exhaustion lowers the immune system but somehow I thought it wouldn't work that way for me. I have a pretty tough immune system. I don't often get sick and when I do, I don't get very sick so I suppose I thought I was ... immune.

In the past couple of months I've taken on a big new project, but I had existing projects I couldn't just drop so during the transition period I'd basically been working 50% more than my usual hours, week after week. I'm pretty sure that's why I didn't just get bronchitis like my husband did.

2. Working at home is still working.

For those of us who work from home, the line between "at work" and "not at work" can be blurry. I often tend to work late into the night, and then sleep late in the morning. I don't always get dressed to work (I'm wearing a sleepwear right now) and I mostly make my own hours.

That doesn't seem so tough, does it? I figure, sick or well, I can make it to my desk, get my fingers to the keyboard, and type out that email or article. Not so much. Concentration takes effort; interviewing and writing isn't easy and all of it takes energy that your body needs when it's fighting an infection. No matter how much I try to tell myself that sitting at my desk and writing isn't much more tiring than lying on the sofa watching The Big Bang is.

3. People are more understanding than you think.

As it happens, the week that I got pneumonia I had been scheduled to interview three highly placed executives in very large companies. They were the kind of interviews that can take weeks to set up, and the kind you really don't want to cancel. But I knew I didn't have the needed brain power to do the job, so before I asked my husband to drive me to the doctor's office, I sent out emails canceling those appointments and more. Everyone was very understanding and most went out of their way to reschedule for a few days later.

4. And when they aren't, you have to set limits.

There was one exception: A client rescheduled a conference call by only 24 hours. He was sympathetic to my illness but the implication was clear: He really wanted me to get the work done as fast as possible. So I dialed in for the call even though I felt awful, my concentration was shot, and I wasn't as much use as I should have been. Next time, for everyone's benefit, I'll set better boundaries.

5. Most deadlines are looser than they appear.

One of the interviews I cancelled couldn't be rescheduled for more than a month. That would put me well beyond the deadline for that job. So I offered the client the option to pass the work on to someone else, which would have been a nice deal for whoever it was, since I already had done the work of setting up the appointments. No, he said--go ahead and turn the work in late.

It made me see that deadlines other people set may be like those we set for ourselves, a day when work must be completed just so it isn't forgotten. Most have extra air in them. Almost all can be changed if necessary.

6. Enforced time off gives you a chance to take stock.

Life is so full of rushing around that we rarely get a chance to stop and think about where we are, what we're doing, and how our day-to-day activities fit into our long-term goals and desires. As I recovered and slowly began picking up my duties again, I had a chance to give some thought to what I cared about and enjoyed most, and what I wanted to do with the rest of my life. Taking time for this kind of reflection is always helpful, at least to me. For one thing, I knew I didn't want to ever work myself sick again.

7. Life always trumps work.

This is a difficult lesson for me, and one I have to keep learning over and over. I was raised by workaholic parents and I tend to put work ahead of everything else, all the time. It's been great for my career, not always so great for my happiness quotient, or my family relationships.

But of all the things I had to cancel only one that really upset me: A scheduled visit my 90-year-old mother who had recently had a mild stroke. I briefly considered doping myself up with antibiotics and going anyway, but bringing a nasty infection anywhere near someone that age would be insane.

It was a good reminder that it's the people in our lives, not the work that we do, that matters in the long run. I'll try and remember that, now that I'm well.

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