You have had your tongue ring for over 3 years you recently developed a little red bump in the actual tongue ring hole it is painful what could it be?

Well it can be a small cut, a set of annoyed taste buds, something that has entered the piercing and is annoying the piercing or a reaction to something you have ingested. Using a good oral rinse, rinse the piercing out twice a day without fail for a couple of days and see if that changes anything.

Barring that you could have a burr on the barbell, remove it and check for any damage to the barbell surface. You should be taking your barbell out once a week and cleaning it with tooth paste and tooth brush to keep it shiny and clean. Plaque deposits can become hard and act like burrs causing oral irritation, so cleaning your barbell should be part of your oral health routine . Your barbell should have been stepped down to a shorter shaft, if this hasn't been done this can cause tearing and irritation, so be sure you have a shorter barbell in during daily wear.