My son fell yesterday.

Yesterday my son fell, he's just got to where he wants to walk the furniture & we crashed out yesterday. I checked to make sure he was all fine and he was. About 5 minutes later you could see that his lip was swelled up a little bit and I checked and it was just the lip swollen.. Well, he has a tooth coming in and I brush his teeth. Well, when I was brushing this morning a purple tint caught my eye and his little gum where he hit yesterday is purple. 😭 I'm a ftm and I know baby's have falls but it scared me when I seen it.. Do you think it's okay or should I do something? Call his doctor? I'm stressing and he's just perfectly fine playing with his toys.