Hi. I'm A 44yr Old Woman With Several Medical Problems.

Hi. I'm a 44yr old woman with several medical problems. I have reactive arthritis which requires an infliximab infusion every 6 weeks at the hospital. Iritis, glaucoma. I've recently been put on blood pressure drugs aswel! But a couple of weeks ago i found a lump under my armpit. My dr put me on a course of antibiotics. She thought it was a boil. I finished the tablets on monday. The lump has shrunk. But not gone, and only today i can feel more pain and something else swelling above the boil. It seems a strange thing to bring up. But i also seem to have swollen gums behind a couple of teeth. Am very nervous. Can anyone please advise? Thankyou.