u/Inevitable_Motor_321

Ok so I have this ball like thing under my armpit at first I thought it was a cyst due to it being hard sort of but there’s no pain I asked a friend to try and pop it and stuff did come out but it feels the same it’s completely pain less but when I feel it it almost feels as if it connects like there’s a long this strong attached it’s such a weird feeling and I have itt pls anyone know what this is!?!?!? Im 22, 5,5 female 231lbs