There may be many possible reasons behind this (eg. He may not be liking you or your body, may be involved somewhere, may have sexual problem, may be revengeful to your initial avoidance etc.), but not the one he is giving. Ask him to involve in foreplay, there is no question of pain in it. If he avoids that also then it is sure that reasons are different then what he says. Communicate with him regarding your desire to have a sex and not baby (question of baby comes after normal sexual life). Consulting a psychiatrist is also a good idea.