I Have A Burn From Hot Tea, It Was A

I have a burn from hot tea, it was a sore just inside the bottom lip. This was about 8 months ago. It got infected, I was on antibiotics for about twenty days. The sore never healed, again but me on antibiotics again, then two weeks ago sent me to a dentist he gave me some paste the sore is starting to heal, but I can feel swelling from my bottom lip down into my chin. It is painful and I can feel hardness under the skin.