As a perfectionist, I felt this in my soul. I too tend to prioritize studies above all else.
Sleep > Food > Studies is a good rule. It is hard when you have a lot going on. Sierepica's advice is good--focus on the big assignments. Especially since you're able to study from home, I would recommend setting yourself timers--work on an assignment for an hour, take a 15 minute break to play some music and dance, work on the assignment for 30 more minutes, take a 40 minute nap, work for 15 minutes on something else, switch back to the big assignment for 30 minutes--it really does help, and you do get some rest in.
Also, if you're having trouble actually sleeping--laying in bed, thoughts racing--it's actually really good for the brain if you lay there and do nothing. Even if you can't sleep, your brain is still getting some rest.
I believe in you!