Fistula, #14 (upper left molar), noticed 4 days ago, but have had sinus issues. dentist said go to endo "in case", but i feel it is an ent issue?

Tooth first: I would agree with your dentist who thinks your problem is tooth related and suggested endodontic evaluation. I am assuming a clinical exam was performed with the appropriate x-rays to visualize the entire tooth. Pain originating from a maxillary molar can be referred to the maxillary sinus and vice versa. Another way to diagnose the origin is for your dentist to track the path of the fistula.

See a dentist: or an endodontist. All fistulas must be traced with a gutta percha cone and periapical x-ray for the differential diagnosis between tooth infection or other infection, like gum or sinus. ENT is not trained to give this test. Hope it helps.

Fistula: If it is tooth related it should show up on an X-ray. It's impossible to say for sure without knowing the history of your teeth or seeing any X-rays. I've never heard of a fistula developing above a tooth due to a sinus infection. Usually it is due to a chronic infection of a tooth or a fractured root.