My girlfriend and I are 23 years old and we indulge in sexual activities not so frequently, once in 2/2.5 months. It has only been a couple of times since we have engaged in a sexual activity. I find it very difficult to penetrate inside her as it often hurts her. Is it normal for her to experience pain during the first couple of times ? Am I doing anything wrong ? We use lube and engage in foreplay as well before having an intercourse.