Mouth ulcer, blisters tongue, red patch.

I had mouth ulcers white patches and i went to dentist he said it was caused by a traumatic bite. There is also a red swelling in cheek and under the tongue I feel like a painful swelling with a blister is there which I can't seem to find but it hurts both the sides of under tongue and also the main vein under the tongue has become reddish. Also near the tonsils behind the uvula I have tonsillitis which has white dot like structure. Normally when I used to have tonsillitis I used to have high fever cold but nothing is there for now except for swelling ridges. Also I have cobblestone throat. I also felt left side pain in stomach and pain in back muscles which I had suffered in an injury long back. The doctor is saying everything is because of Gas. He thinks it's GERD. But can gerd cause mouth ulcers, painful blisters near tongue and cheek lining, strep & cobble throat  ridges behind uvula. I used to heavy smoke for 4 months 5-6 a day so total 700 cigs in 4 months. Should I get a biopsy?