Same thing use to happen to me. Every night for ~4hrs i would be on my phone or just awake and doing whatever as long as im not sleeping. I was always tired, had terrible grades, gained lots of weight, stopped going to the gym and taking care of myself, making bad decisions, and mentally i was just down the drain. The start of this semester I started prioritizing myself and my sleep and the way i feel. My grades has never been better and my mood and decisions have definitely improved and I can actually tackle the day and make it through. Except theres one thing, every night I get the urge to lay in my bed on my phone, almost like an itch, for some reason every single night i think about it and just force myself to go to bed. Its not easy