You seemed normal and these problems appeared overnight…I’m agreeing with “toomanytabs” that you sound young.
What level are you in school? What you are describing is kind of where I was going from high school to college. (ages 17-19)
Looking back, going from the rather monotonous elementary and high school experiences to college where everything was “completely my responsibility” was too much.
All of the coping mechanisms you might’ve developed are being tested big time.
Does your school (or some clinic near you) have a drop-in/”emergency” counselor? Depending on how soon in August your appointment is, you could be going on feeling the same way for several weeks…which can’t feel great. A one-time session just to vent and get some guidance on stress management could help… [Emergency counselors aren’t just for suicide or potential crime interventions (although those are priorities: a session I had once was interrupted for just such a situation), they are for “I need to talk something out and don’t think it can wait for 2 months”.] Do that before you chew your nails too far!