I am a 19 year old male. I recently discovered when i raise my right arm, there is a 'lump'. However, i cannot tell whether it is normal as in a muscle or bone from my shoulder area or indeed a lump. I can see it when i raise my arm straight up, and it is kinda in the area where the arm meets the center of the armpit. It is rather large, around a golf ball size. On my left arm there is a very similar 'lump' but just a slight bit smaller. Is this just a normal muscle or something, or is that not a normal thing for the armpit. It started feeling tender, but I keep getting nervous and poking it so I think that may be what is causing that. Sorry if this was a little confusing. Also I think this may have been here for quite a while, I just am nervous and cant remember and am just trying to make sure it is alright.
Thanks for any help,