Bad taste in mouth....

[OhWhatAPalaver]

Dentist says she can't see an infection but to me the the taste is the same as when I've had infections due to wisdom teeth in the past. The bad taste (and smell, ugh) is coming from right at the at the top of my mouth, near where my wisdom tooth should be, sort of the top of the gum/inside of cheek near my molar but the molar itself is fine apparently. It's been coming and going for a few weeks and now I have some pain and pressure, which the dentist says will be caused by my cold (full of a head cold atm). She also said it could be my wisdom tooth trying, and failing, to come out.
My concern is the that she seemed in a rush when she was looking, I was the last patient before lunch time and she was running late. The bad taste seems to me to be bacterial and I'm worried that it will get worse, what can I do other than corsodyl/salt water and should I get a second opinion? TIA.