My Boyfriend Gave Me A Hickey/love Bite On My Left

My boyfriend gave me a hickey/love bite on my left breast and once the hickey started fading a lump appeared, it's been a couple weeks and it's only shrunk a little and doesn't appear to be going. I have not yet been to my doctor because, in all honesty, I'm very scared and worried over this and don't want my mum to know just yet