Exact same thing happened to me, except it ended in emergency surgery for me! I think especially menstrual cups and iuds are no good together because of the suction the cup can create.
Wow my ex friend and ex roommate tried to pull this with me over a 40 year old dude( we were 25 at the time) They weren’t even dating she just thought she might like him. I was also wearing a white t shirt and am extremely flat chested 😂 I wish I had grown a backbone before moving in with her