I pierced my lower lip about 6 years ago & a few years back I took out the ring. the hole is still there but there is nothing in it.

I performed oral sex on a girl a few days ago & the next day I noticed a kinda sore feeling around the outside of the piercing, about 2 days later it formed a kinda hard scab that peeled off, everything is ok now.

can this just be a coincidence that I got this scab after going down on the girl or could it be something with my mouth?