Age 16. no family history of disease. she woke up with a bruise looking spot on left breast w/ no pain or lump. nothing, or serious? could it be ibc?

Breast spot: given her age - 16 it is likely nothing. IBC (assuming it to be inflammatory breast cancer) is relatively rare - see http://www.cancer.gov/types/breast/ibc-fact-sheet and has other symtpoms Could this be a bruise? or and NOT suggesting anything - a hickey?? I would monitor it over the next several weeks - if it resolves I would not be worried - if it progresses - get it checked