Rani, you have nothing to be worried about, except maybe getting pregnant. Your love for each is not uncommon, and there are many of us who have incest with our real brother or sister. Your relations with your brother are not incest if that is your concern. It is probably best that you try to keep the intimate details from your parents till it becomes obvious that you are in love or if you get pregnant. If you decide to marry later on after you finish your education, there is no danger in having children, and it is not unlawful.