What is on my sons tongue?

My 21 month old has a strange rash on his tongue. He is teething right now several teeth and slobbering a lot but I mean could it be from his pacifier🧐 could it be an infection?

He doesn’t act like it bothers him at all but it looks irritated and uncomfortable. Should I take him to the walk in clinic tomorrow since it’s the weekend?

There’s no white spots in his mouth. His bottom lip looks irritated on the inside too. There’s no rash anywhere else on his body.