Blister on baby’s gums, Help!

My little guy is 6 weeks old. I just noticed this weird little blister/bubble where his gums and lip meet. It looks almost like a little skin tag. It’s reddish. It’s moving around slightly when he moves his mouth, I haven’t felt it because I didn’t want to put my hand in his mouth.

He is bottle fed.

The picture isn’t great because he was very angry that I was trying to open his mouth 😛

**i will be calling the pediatrician in the morning when they open, I was just hoping someone could speak up if they have any idea what it is, just so I can get through the night not thinking my baby had cancer or something in his mouth 😓**