...as I know many do. I 'think' it is the ms with me. I will go several weeks sleeping well, then go several weeks hardly sleeping at all. Meds haven't changed. I have been experiencing this for years, even when I worked full time and should have been exhausted. That was before my dx. But that is why I think it is part of the ms. I don't know for sure, but I know how you feel. My only difference now is, that I'm retired and I have learned just to take the sleep when it comes, no matter what time of the day it is. Right now I'm on not much sleep.
I hope you get some good sleep very soon!