Saying "I need to catch up" can be a recipe for failure. The problem isn't that you got behind. The issue is that it is impossible to truly catch up. Sleep experts say you can't catch up on lost sleep, just as much as you can't get time back. Worse, it gets you into the wrong mentality for future productivity.
You are setting yourself up to always be behind.
Imagine starting your day saying you need to catch up. When you think about it, it means you already believe you are behind. This only ups the pressure to perform, and even if you did "catch up," it implies that you still wouldn't have started the work that was supposed to be done today, rather you completed what you felt guilty about missing yesterday.
Instead, focus on the must-dos that will truly accelerate your progress today. Prune your to-do list to things that have to be done immediately to move forward. Is there an item that won't make a difference whether done immediately today or next week? Push it down the list.
You are feeling shame rather than excitement
You may have procrastinated, been ill or simply been away. The catch-up idea can easily trigger shame, which is you feeling bad about yourself, or guilt, which is you feeling bad about what others may think (I share more in my recent TED Talk, on perfectionism).
To actually be more productive, consider what you're looking forward to: Getting feedback from your important client, creating a new revenue stream for your business or finally following up with a VIP. If you feel stuck, try doing this simple gratitude exercise.
You are pushing yourself closer to burnout
Doubling up on your work expectations and expecting to get twice as much done is like doubling the oven temperature and wanting the cookies to be done twice as fast. Suddenly doing 16-hour days in lieu of 8-hour days won't necessarily get you there faster, but it will certainly increase your chances of burnout.
As an alternative, try actually working less and strategizing more. Taking, say, an extra 15 minutes in the shower, on a walk or meditating can give your brain the room to determine the most effective next action.
You want to shift from reacting ("I need to catch up!) to responding ("I need to focus on this to make the most impact."). The results will speak for themselves.