I'm a 15 year old Female, i have had 2 lumps in my right armpit and 1 lump in my left armpit for almost a year now. The lumps do not hurt, but every once and a while they swell up and turn red but after about a week they return to "normal". When i pinch them a tiny bit of hard pus comes out. The lumps are raised but i can feel them under too. they haven't grown at all. I'm not sure if they are lymph nodes but they are aroung the area that my lymph nodes would be, so could it be some kind of cancer?... I just wanted to know what it could be and if i should be concerned.