I Have Swelling And Tenderness Under My Left Arm In

I have swelling and tenderness under my left arm in my arm pit. it hurts to touch especially in one area. When I look in the mirror it is defiantly noticeable there is a difference from my right arm pit. Also along with this my breast are tender and hurt all the time especially when touched. Sometimes its even uncomfortable to wear a bra. at first I thought it was just signs of too much caffeine. but I stopped drinking caffeine and it's not any better. It seemed to progress slowly to this point to were it now hurts all the time.
Should I be concerned enough to see my doctor?