I Recently Got My Tonsils Out 3 Months Ago And

I recently got my tonsils out 3 months ago and with in the past month I have found a small transparent blister on the right side of my throat in the same spot. I only ever notice it after I eat. The times I noticed it were after I eat rice and chicken, chicken nuggets and fries from a fast food restaurant, and pretzels. the area around it is red and there is also a white patch right next to it. It is very uncomfortable.