Small lumps in armpit and arm

Hi,
Welcome to the forum. I am really glad to help you out.The small lumps sound like an infected hair follicle causing boils or swollen lymph nodes. Boil is usually due to plugged sweat glands that become infected or by an ingrown hair. The bumps can also be due to a swollen lymph nodes which are common after a viral or bacterial infection and boil is caused by a bacterial infection. They are basically caused by infection of the hair follicle by staph aureus. Apply warm compresses on the bumps and keep the area clean.

Drainage of the bumps is done only when it becomes soft and forms a head. Take some over the counter pain reliever and consult a doctor for examination and antibiotics prescription. If there are recurrent bumps, then please get your blood sugar levels estimated.

I hope it helps. Take care and regards.