I’m a 16 year old girl and my mum has never had breast cancer but other members of my family have. I may be overthinking this a lot but under my armpit there is a small lump and it hurts a lot like so badly. I never noticed the lump before and it only started hurting today. It is definitely not an ingrown hair or a shaving scratch or anything like that there is just a small lump under the skin which hurts a lot?? Should I wait a few days to see if it goes away or should i see my gp soon?