I'm really worried because I've got this lump in my left armpit, and it's almost as big as half a table tennis ball. It's really painful, with sharp stabbing sensations. Plus, my left breast hurts a lot too, from the nipple to somewhere inside, with sharp electrical pains and then other times, it's a continuous dull ache that sticks around for hours. Which type of doctor should I see for this? And do you have any idea what kind of tests I might need?

it might be an abscess, consult a surgeon