Seeing a dentist is advised.
Please do go to your dentist. I had a similar infection in a front tooth and after it went away, I did nothing. Fast forward a couple of years and I have now lost the front four teeth due to bone loss from that former infection. If you don't take care of it properly the first time, you can really suffer consequences later.
Please see a dentist.
go to the dentist so they can clean it and find out what is going. you will lose your teeth if you don't do this sounds like you are in need of a root canal on that tooth.