Hello

I have posted my question on some other forums but unfortunately received no answers, so I am really hoping to find help here. I have visited my dentist 4 times in the last fortnight so I'd like to get some other opinions before booking another appointment.

Several years ago I had a root canal treatment done (bottom right premolar). About 2 weeks ago I started feeling some mild throbbing pain. Made an appointment, Xray showed infection. Dentist removed the feeling (I notice hairline crack in it before so I suspect this is how bacteria got in), cleaned the canal (honestly it took about one minute) redressed it and told me it would settle soon. It was a Friday. It did not settle, it fact it hurt so much I thought I was going to loose my mind. I went back on Monday, was told the previous cleaning process "stirred" the infection, was given antibiotics (15x 250mg of amoxicilin). The pain was very strong, my cheek and gums swollen.
Additionally, my front tooth (top) suddenly became VERY sensitive to touch, really raw, as if nerve got exposed. Does anyone know why?

After a few days antibiotics finally kicked in, the pain almost gone away, the area was just tender. When the swelling gone down it revealed hard lump in my jaw, like a marble. Underneath that affected tooth, but not in the gum, it felt like in my bone. It didn't move. I went back to see my dentist. He told me it was still an infection, to continue taking antibiotics. I finished taking them and went back in because the lump was still there, didn't change size or position.

I asked the dentist to take this tooth out. I lost days of work, I am a single mum to two children and the pain and complications were really affecting our lives. The tooth was extracted on Tuesday afternoon, so 5 days ago. I was told the root was long, to expected soreness etc. I was in terrible pain for 2 days, then it calmed down and today is the first day without painkillers. It's a bit sore still but I think it's healing fine. The sweeling is still present but nothing major. However, the hard, marble-like lump is still there. Still same size.

Please help, what it is? Should I go back again? He has seen it several times now and didn't seem concerned. What would you do?

Thank you so much for any input you can offer!!!