I very often get a really bad mood swings I

Patient: I very often get a really bad mood swings. I usually work 3 or 4 times a week from 5 to 9:30. I got school from monday to friday. i usually sleep about 7/8 hours everyday. i really don’t know what to do. I got really tired and annoyed when i came home from school but i was fine at school. And i often play with my phone every time i’m awake and when i want to go to bed. i often get black-out as well like when i laying down on the lounge for 15 mins & i got up i just can’t see anything for like 5 secs & sometimes got dizzy as well. Is it have to do with all that i been doing? Please let me know how to handle them.

Doctor: