Hi everybody. Hope this is the right spot for this, it seems to be?

I've mentioned to my dentist a few times that one of my upper molar teeth is bothering me. It feels as if it could have a cavity- it's sensitive to cold and it just generally hurts (throbbing sort of pain) sometimes? It hurts right in the center like it would if there was a cavity. If I feel it with my tongue it feels different from my other teeth, (rough sort of?) but my dentist has looked at it multiple times and they've said nothing is wrong. It's not very bad pain at all, moreso just an annoyance, but I have major anxiety about my teeth. This has been going on for probably over a year and I'm not sure what to do.

Has anyone else experienced anything similar? Thanks