Why does this keeps happening?

Hi! Even when managing ocd I keep having this faitgue. Today I woke up, studied for 1 hour and had to take a nap, woke up and feel tired. This haves been going for a long time. Went to exercise which is what I love and had to quit today because my lifts went down and I couldn’t handle the tireness.

All I want to do is sleep and feel tired. When what I really want to do is be active, study with energy, and smile.

I sleep for 7-8 hours (wake up twice to go to the bathroom) + naps.

I’m trying to avoid the symptoms but it’s extremely hard

Also, I have mood swings throughout the day and energy fluctuation