Try making up routines and tasks for your high and low energy days. If you know you woke up with low energy don’t pressure yourself into a 3 hour study session. Watch a slide show do flash cards make the task fit your mood and energy not the other way around.
My advice to unmedicated adhd/audhd students is CUSTOMIZE EVERYTHING. If you can’t get an IEP do things to accommodate yourself. Bring your fidget toys get loop ear plugs if you notice things like the sound of the lights bother you. They aren’t earbuds so you won’t get in trouble