Getting a second opinion is probably a good idea. The other issue is whether or not you are adequately aroused. As women it takes awhile sometimes, but the foreplay is absolutely essential. Mostly it is important to relax and take things slow and easy. If you are really dry lubricants can usually help. The vagina is capable of expanding enough to allow a baby to pass through. so I suspect it can handle almost any size penis, given enough time. Sex with the one you love is an awesome experience, but it is essential that you have a trusting and loving relationship. Fortunately my husband is patient and very concerned about making it good for me as well as for him. Outside of a committed relationship as in marriage it can be pretty traumatic at the worst and not very fulfilling at best