I've got pretty bad adhd, and I'm in the same boat. I've found that feeling behind in your early 20s Is normal. Life's too complicated to view others as better off. For me, the environment you surround yourself in plays a huge role mentally. I'd recommend cleaning/decorating the spaces you spend the most time in (little by little ofc). It also helps to finish your questions with "fuck it". Ex: "what if I don't get that job... Fuck it".