My boyfriend has just recently got a big red bump come up under his arm and It felt like it was full of pus and the pus felt really deep into his arm. Well he cut a potatoe in half and stuck it on the bumb and left it on there all night long and the next morning it had popped and pus and blood was running out of it. Well a few days later it started hurting him again and now there are 2 big bumps and about 4 or 5 small ones with white heads on them. He can barely hold his arm straight down cause it hurts him so bad. Someone please help us.