Hello. I Am 18 And I Have Had A Boyfriend

Hello. I am 18 and i have had a boyfriend for 3 years now. We want to have sex. But in my culture i can t do it. I am afraid that i ll regret it. I m afraid that i would regret doing it with my boyfriend which i love very much and willing to spend the rest of my life with. Anyway can you please give me any advice. What should i do?