Hello,
If your friend had intercourse close to periods, then chances of pregnancy are less. Pregnancy occurs only during the time of ovulation. Ovulation is the release of a single, mature egg from a follicle that developed in the ovary. It usually occurs regularly, around day 14 of a 28-day menstrual cycle. Intercourse during periods will not result in pregnancy as the uterine endometrial lining has already been sloughed off the uterus.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.
Very likely if she used no protection and is not on the pill she has a very high chance of being pregnant. Hope all the best for her