I'm always surprised by how people can be extremely productive. The only thing that moves me are dead lines, but at the same time it builds a ton of stress. These days everything looks bad, rushed and tiresome. I tried taking caffeine pills to, at least, remove some of my sleepiness; but I do not recommend, more negatives than positives.
I imagine that you're tired of hearing this, but exercises can help a lot, if you can do them.