Don't expect yourself to be productive all the time. Efficacy and productivity is for constant for the brain cells and I have accepted this fact. The world is moving at a rapid pace, we are fighting with the world and our insides at the same time. Hence, pushing yourself seems like the thing to do but it should not be the at the cost of one's wellbeing or rather it should not be the only thing to do at all times.
I hate it when people overcommit and then push themselves until they're exhausted mentally and physically. Organisation and prioritisation is the key to deliver efficiently rather than over committing and it's okay to be clear about your 'YES' and 'NO' right from the start. People usually hesitate clearing such things and loosening up to please others but I always believe in smart and efficient work over more work.
I am feeling burnt up right now even though I didn't do much today but it's best to come to terms with the fact that not all days are the same. Things that work for me:
You deserve it!