Assuming that is what I am seeing... and I've not seen a doctor or anything... but lets just assume that I have correctly identified what is inside of my cheek.
From what I've read, canker sores are really no big deal.... right? I mean, I shouldn't stress out about it, right? I've read they aren't contagious. So, I couldn't have caught it from someone, and MORE importantly I can't give it to anyone, right? If I give oral sex to a woman while I have a canker sore present, there is not chance (in the same way herpes can be spread) that it would affect her vagina, right?
Providing you are sure it is a canker sore, there should be no problem with oral sex. A cold sore on the lip is a different story, though.
Canker sores are ulcers of unknown origin on the mucous membrane. A cold sore is a virus (herpes simplex to be exact) and can be contagious.
What you have said is correct.
As long as you are sure it's just a canker sore.
Best to you,
Gellia