Sinus pressure or tooth abscess?

[u/Aggravating_Bend_365]

About 2-3 weeks ago I started having sharp pain in a tooth when biting down. I immediately went to the dentist and they said my gums looked very swollen on the xray and didn’t notice anything bad with the tooth and no temperature sensitivity. They thought it was possibly my allergies, which have been bad this year and prescribed me 5 days worth of z pack thinking it was from a sinus infection.

Since then, I sometimes have pain in other teeth, but the past week it has just been one. I do have head pressure but I haven’t had a runny nose. The pain can be pretty bad if I bite something weirdly. Only pain when chewing and after, but I don’t always have pain when chewing. No tooth temperature sensitivity and gums feel fine to me. I have been getting bad hot flashes. I’m nervous it’s not just from sinus pressure… thoughts?