Might be TMI, Having internal issues

(TMI) So I'm 32 w and 4 days with mono/di twins, and today while showering I noticed something I haven't before.. I noticed a ball shaped.. (thing?) right on the inside of my vagina. It's big enough to feel without having to put my fingers in far at all - about the size of a gumball I'd say, right at the opening. I feel like my insides are starting to fall out something, as I've been having pelvic pressure for about a month now 😯 Just wondering if anyone has and idea what I'm talking about or has dealt with anything like it.