Oh god. I feel for you so bad. Whenever I (think) my body even regresses slightly I get really paranoid. But the bottom line is, you did this to yourself and now you have to fix it. Although, the diet required to make gains at uni is so expensive for a student but not an excuse to stop eating. Buy tinned tuna and cook chicken breast.
Oh and stop smoking weed straight away. It's doing nothing for you bro.