Can you get cancer at 15?

I'm 15, overweight, maybe even borderline obese, and i've lost 10lbs in the past 3 weeks. I was feeling down because my are so big when I spotted a red bump, and it hurts the slightest if you press on it. I was worried because my mom's cousin has cancer, (my mom calls her my aunt because my mom was adopted by a family friend) I have a DD bra size, and I think I might have cancer. My s are always lumpy I think that's just the fat. I also had like these scales on my which looked weird and no one could diagnose (on Y!A). Anyways, I've been away from home for a couple of days so maybe it was just something from their house? I'm hoping its not breast cancer but it looks like it has micro veins all going towards it. :S