Hi everyone!

I dont know how I came across this lump (if that's even what it is!) I feel like maybe I should go to my gp but i dont want to waste anyones time! It's not like a pea or golf ball more of a flat swelling on my breast bone just above my bust. I'm so confused and wonder if I'm just making it up in my own head! My partner said he can feel something but not drastically! It wasnt sore at all but now it's really tender because I've been prodding and poking it none stop trying to feel if there really is something there or not??!!! Has anyone else felt anything in this area before? Is it classed as the breast? Oh God help I'm driving myself insane xx