This kind of bump can be a swollen lymph node,a sebaceous cyst or a boil. Lymphadenopathy (swollen lymph nodes) is usually caused by a viral or bacterial infection along with other numerous causes. Sebaceous cyst is usually painless but can become painful if infected. Then antibiotics are needed. Boils are caused by infection of the hair follicle be staph aureus.
Please keep the area clean and apply some topical antiseptics. Also wear loose-fitting cotton clothing and use an antibacterial soap or mild soap like dove. Avoid any kind of cosmetics. Topical antibiotics such as mupirocin or neomycin containing ointment are also useful. In case the symptoms persist then oral antibiotics may be needed. Please consult a dermatologist in that case.
I hope it helps. Take care and please do keep me posted on how you are doing or if you have any additional doubts. Kind regards.
I had a small round lump near where my underwire ends near my underarm. Not too painful. Thought it due to my having gained 10lbs and my bra becoming tighter (i.e., rubbing into an irritation). It went away within a week on its own. As soon as it did,, two more (exact same spot under both arms). Super fast...went to bed fine, woke up with dime size Painful bumps. Over next two days one filled to the shape of a Hershey's Kiss. Dr. lanced and drained one (immediately felt better), gave me antibiotic injection in my hip, been taking Bactrim since (4 days). Yesterday I got an email from the man I'm dating (intimate with) and he says he has a few small, painful bumps under his arms. He said "you are contagion". I have not received a call from my doctor telling me what the labs said. Any thoughts on what it is/could be and how it jumped from me to him? As you might imagine, he's unhappy and I can't blame him. We are in our mid 40s, advanced degreed professionals, and we aren't intimate with others. Could this be someone's past coming back to haunt us? Your thoughts please. Thanks.