Hey, I can totally relate!
Maybe start doing your work kind of earlier, or get a head start in school?
but also someone once told me
"A little concern is good, but do not allow that concern to turn into stress"
But a little tip from me would be to just before you go to sleep, close your eyes for 5 minutes and think about something you really care about, something that happened to you that made you happy on that day (even the smallest things) and go to sleep feeling happy (trust me it works lol and i used to have THE worst sleeping schedule, I would like go to sleep at 3:00 sometimes because i could not sleep or i had lots of stress and work to do)
:) please don't stress anything, because both you and I know that you try your best and you will do great! so don't let that get into the way of your sleep!!