mstia
I'm sorry I don't have any answers for you but sure do sympathize.....because I know what it is to have a toothache. Way to go by not breaking the fast, you are a very strong person!!!
As far as the cold sore it is probobly the toxins getting stirred up and coming up they have been known to cause skin rashes, pimples, cold sores, and lots of other things.
I hope someone answers your post that can help you. Have you had good energy up til now? Maybe your energy level is down because your body is trying to fight the infection/poison in your system.
Tia