Breast lump?

So I’m 14 and yesterday I noticed a lump about the size of a golf ball in the inside of my right boob right under the nipple. That boob is also gotten bigger and my nipple area is more sideways.

I doubt it’s breast cancer because of my age but my paternal grandma had it.

No rude comments please. I don’t have a female in my life I can talk to it’s just me and my dad and we don’t talk about that sort of things.