Quality vs. Quantity
Think about this question for a moment-Is it easier to put more time into something or to improve the quality of something? In other words, is it easier to do more (work faster) vs. doing better?
Doing more is an investment of time but doing better is complicated. It takes learning, brainpower and trial and error. In fact, doing better can require an investment in time as well (quantity). Maybe it is time to slow down and assess the quality of the work that you are producing. If the quality of work is related to the things that are most important to you then the quantity isn't going to be as important.