I think Something is wrong with me.

Okay guys the other day I was fingering myself and got really deep. I noticed I have a weird thing up there. Its hard to explain but basically it’s feels like I have a nob with a little opening (kinda feels like a mini butt hole) and I can go in deeper on each sides. Is that normal?? Or am I like a man or something??? !!!UPDATE!!! Thank you all for telling me what it is! So when I have sex (that will obviously be in a while) does the dick go into the Little hole at the end of the cervix?? Or does it go to the side of it?