Help!!!

But last night my boyfriend felt a lump it feels like a bean kinda and it's not my cervix it's in the start of my vagain on the roof my vagina more or less in the beginning of my vagina and he made me feel it as he was concerned and I am too ! What could this be? I think it's been there for quite a while but I've always been oblivious to it I'm not sure , But is it something I should be concerned about or does anyone have the same thing ?