Sex is likely to be uncomfortable if she is not relaxed and aroused. Make time for foreplay and try not to think of penetrative sex as the main goal, as penetration will be painful if the vagina is not lubricated. Can also try using a lubricating product. If still finding it difficult to have sex, there may be an emotional reason or anxiety that's causing problems. Also, pain can be caused by a variety of things, such as an illness, infection, or a physical or psychological problem. Speaking to a counsellor or sex therapist can help deal with underlying worries.