I know it's really difficult when you have a sick child, but the first thing you must do is to stop freaking out. That won't help the situation at all and will keep you from being able to think clearly and rationally about what the best thing is to do.
Fevers do serve a purpose as part of the way the body heals itself. That is not to say not to take him to his doc if you feel it's unusually high or he has other symptoms. That's your call and not always an easy one.
If he seems uncomfortable, you can always use cold wash clothes on his forehead and wrists and that can have a cooling effect.
You can always call his doc to inquire the best thing to do once they open.
Most of all, get yourself in a calmer place so you can be there for him in the best way. - Take care.