Love has to be painful because it is so deep. You are making an emotional, physical commitment to another person that innately empowers them to hurt you even if they don't mean it. So love, joy and pain sort of all come together. You will have to trust that your lover will only want to give you joy. So your task is to ask him what happened.
Every human experience is on a bell curve from minimum response to maximum response.
Some women are explosive in their orgasm and some women are much more internal and quiet, but that doesn't mean that their orgasm is lesser. Every woman and every man has their own unique response to orgasm, so enjoy what they do and learn to read their signals. Women having orgasm during intercourse is a highly variable experience and many times it takes repeated exposure and comfort to surrender to orgasm, so I wouldn't worry about it. Just make sure you are responsive to her requests and that you do the things she would want you to do. To some extent it is dependent on age and gender.