Hi there, I have been suffering with this too and today I i just couldn't take it anymore. I called my dentist and he could not fit me in until Feb 21st - well NOWAY would I make it that long without going insane!! I just called another dentist and explained my situation and they got me in this afternoon. YAY!! Maybe if you call around you can get lucky too!

Oh also, the dentist DID drill it out so it could drain (gross) and it feels 100% better. He can't fill it due to the infection or do a root canal, but at least it is not killing me like it was - just like you with my whole head hurting and I could barely think straight. I told my husband I'd rather go through labor again!! LOL
GOOD LUCK!!!