<s>[INST] hello! Tonight I noticed a small non painful lump in my armpit. It is about the size of a pea and does not hurt at all. I also started my menstruationn tonight and I have read that these can sometimes go hand in hand. I can gently pull at the skin in my armpit at the lump comes with the skin and I can then feel it all around. It is pea sized all round and feels like a hard sponge [/INST] Welcome to Chat Doctor .1. Generally there are carbuncle / furuncles seen in that area. 2.Do to infected hair follicle.3. Avoid blade shaving for some time and usage of after shaves. Trim the hair if necessary.4. If it read and very pain flu get a course of antibiotics, and usually it will resolve.5. Nothing to worry it's just a localized infection / inflammation. Hope it helps you. Wish you a good health. Anything to ask ? Do not hesitate. Thank you. </s>