Do more of this
If you feel exhausted, the problem might not be that you're doing too much; it might be that you're doing too little of the things that make you come alive.
Squeezing harder to get more done only works for a little while. At some point, you run out of energy. Again, motivation isn't always the answer. It's possible to be fully committed and totally out of energy at the same time. So, if you need to sprint for a little bit, go for it. But if you need to keep up a strong pace for a long time, then you need to figure out how to put more fuel in your tank.
It could be deep things, like quality time with your family or close friends. Or it could be simple things, like listening to a great song or watching the sunrise (or sunset, for night owls like me). Or it could be silly things, like a pair of socks that you love (or playing board games, in my case).
We often make plans for all the output we need to do, like making lists of all the things we need to get done and goals we want to accomplish. In order to be able to do all of those things, we also need a plan for all the input we need. The highest quality work comes from living a life that is overflowing with energy.
What fills your cup? What's your plan to keep energy flowing into your mind and heart?