Hi, since it is the first time for your girlfriend she will experience some pain
and also bleeding. To make her more comfortable I suggest you take things slowly and gently and use some lubricating jelly or coconut oil before the intercourse. Despite these precautions she may have pain or be uncomfortable. Regarding the pregnancy
please follow contraception, either by using condoms or even oral contraceptive pills like locate etc. But whatever you decide I suggest not to skip out on good contraception if pregnancy is not desired. Hope this information has helped you. All the best.