Shallow Vajay???

Guys! Help me out! I tried the nuvaring and it kept sliding down. Even when I pushed it in as far as it would go, it still seemed strangely close; when my doctor said you can have it in during sex and the guy wouldn't notice! So of course... I called my Mom and she said she has a "shallow vagina" too. As if this is common knowledge that I should have known about?! Lmao. Somebody puh-lease tell me if they have ever heard of this??  And have you had unfortunate experiences because of it? Does it effect your sex life???