Gum Ulcers Big I'm Pregnant And Have An Infected Wisdom Tooth. I'm Wondering What The Big Blister Behind It Is.?

I'm pregnant and have an infected wisdom tooth. I'm wondering what the big blister behind it is.? - gum ulcers big

First there was pain and then I saw a lump in my throat, like a swollen gland or something. My jaw hurt and got to the point where it was hard to swallow. I went to the dentist and a plate with some of my gums around the teeth and put me on penicillin and Tylenol with codeine. Now 3 days later, finally able to swallow a little easier, but I have ulcers on the tongue appeared, and a large white patch behind the wisdom teeth. What is it? This is a large ulcer or what?