What Could Tender Breast With Bruises Suggest?

Hi, may I answer your health queries right now ? Please type your query here.Hi, I'm a 35 year old black woman. I took a pretty hard hit to my left breast, it was bruised for about a week and tender. I've gone to my gp and he's described it as thickening & scheduled a mammogram. Could it be cancer, or scar tissue? The hit happened about 3 months ago...