Question about stretching...

My husband & I like to stretch my “area”. I noticed the past couple days that even the dildos that we’ve used before don’t wanna go in. It actually feels like the dildo are hitting that part of my pelvic bone. I have noticed it a couple times before but I don’t remember what part of my cycle I was in.

When are also TTC & I’m in the TWW.

Just wondering what would cause that? Thanks in advance.