Okay, well, I think I may have come across a little more aggressively than intended. This is what happens pre-caffeine...
Ultimately, what always helps me under pressures of compulsive, existential thought is just doing things. Perhaps reminding yourself of the realities of your present situation can help keep perspective from inflating to unreal proportions. Life and existence and the enormity and incomprehensibility of it all aren't really all that important when going to the bathroom, eating a snack, watching a show, going for a walk, finding something interesting to read or whatever. Regardless of all that other shit, if you enjoy something, the big secret here is that you ENJOY IT. Fuck anything else. Exercise some of your free will. Acting out doesn't always have to be self-destructive, negative, or harmful. It's the wall between adolescence and maturity. You find the power of your own decision-making capabilities and understand the relative importance of their consequences. Own it.
Okay, getting off the soapbox now.