So pleased you are are feeling a bit more human. It will continue, be kind to yourself and give yourself time.
Yes, the overdrive thing.....me too, in the past. The hardest lesson I have had to learn is how to steady myself down, break the habit of always being on the go. No wonder our bodies just rebel and MAKE us stop, something as radical as depression to force us to listen to ourselves and do something about it.
When you are feeling a bit more able to cope rather than just get through the days, try some relaxation techniques, until you find one that helps. I had to practice daily, making myself take some time out. I surprised myself, after months (well,years) of struggling to switch off, I got quite good at getting rest, my mind got better at relaxing, and, touch wood, I think I am almost there, the fear is going, even when extremely tired, I dont' respond with panic, just normal tiredness, and the knowledge that tomorrow will be better once (not 'if') I have some sleep.
Thinking of you, is it PND? I don't know anything of your history, but reading your post, wanted to give a bit of support. Been there with the sleep probs. whatever triggering factor. LS