No, that should really not be your experience. I can only echo what others say: talk to your doctor. If you think about that your vagina should be capable of giving birth as a absolute maximum, an inch of a single finger should not hurt if you are turned on at all. Don’t be ashamed - i’ve met multiple women who had issues like that and were able to overcome them with medical help, and if your partner is worth the trouble, he will be supporting you because he wants you to enjoy sex too.