pain!?!NEED SOME HELP?

about 2 years ago i went to get my checked out cause i was having pains in my left .my doctor found a small bump which i had felt as well.i got all type of tests and everything came out ok.either way my doctor thought it was best to remove it.i had surgery set up for a month after.in between that month i got pregnant so i never got the bump removed.2 years later im getting these pains again.bump is still there but now the pain is also in my under arm next to my .my grandmother had cancer and my great grandma had cancer as well but not in the breast(partly the reason the doctor wanted to take care of it) what could it be!?!?! and should i go get it checked out??? SN:im 21 yrs old