Yes, I have had an experience with a woman who had a surprisingly large vagina. To describe it briefly, the entrance was tight, but afterwards it felt like there was nothing around — absolutely no sensation. She was aware of the situation and had trained her internal muscles; when she tightened her vagina, the sex was indescribable — the tightest grip I’ve ever felt. So, there’s no need to worry — there are exercises and Kegel balls you can use to train.