Hey sleepless, I'm sorry about school!
Not sure if this would help, but don't think. Example: Ignore that you roam alone in the halls. Take it as an opportunity to venture the school. (Honestly, school is so different
when people aren't around.)
Also, keep your head up, and I mean this semi-literally. Looking down doesn't only brings one down, in my opinion.

Since you're behind in school, maybe stay after class to talk to a teacher about some assignment or something you have a question on. Just the one on one attention would make me feel appreciated, and start to build up my spirits.. (imo, of course.)

It's not about having a good day, then a bad one. You can consistently have bettering days by building happiness slowly.

Also, it wouldn't hurt to take a day off to sleep, not worry about school, and so on...

Anywho, I hope you smile tomorrow because, well, I'd really like you to have a super awesome day tomorrow.