This sounds more like balanitis than it does herpes. You need to go be seen by your provider. The school nurse can't really help you with this and frankly I'm sure you don't want her examing your private parts anyways.
Talk to your dad and tell him you need a doctors appointment today or tomorrow. Don't put it off or it could get worse.
grace
I agree with waringblender, if you have no way of getting to a doctor, see your school nurse immediately! Or maybe a friend could drive you to the doctor or an immediate-care center?
Good luck,
Em
Is there a nurse at your school you can see? If you think you have a medical problem, you need to be seen.