I found a wierd spot on my left .(Not a lump)Could I have Cancer?

I am 17 and on my left near the nipple I found a spot, it is like a reddish pinkish circle almost like a freckle but not brown at all... It is not really big... like the size of half a skittle... I found it one week ago... I don't want to say anything to my mom if it is normal to get these things or something... My mom had cancer on her left and it spread to her lymphnodes when i was only 6 months old (she was only 39) and the dr said she wouldn't c me turn 2 yrs old, but she did she is in remission now... so i don't want to worry her over nothing... I am healthy and have normal periods and stuff like that... could it be cancer? should i say anything to her?