Hello,
I have a small pea size lump under my armpit, I believe this is the second time I get this, and this time I got a week after my period. What could it be? I have been going to the gym and sweating a lot...could that be it?? I read several comments that maybe it occurs around or before your period but I got my period last week....I think last time it lasted about 3 days....I think, I really wasn't keeping on eye on it since it was the first time but this is the second time and now I'm a bit concerned. Please let me know what you think.
Thank you very much.

Best Regards,