Advice please.

I am 19. I am engaged, and he is 20. He is about to be 21. We met in high school, and we've been together awhile. I have never been into hookups, or dating just for fun. I've always wanted a serious relationship. I had to mature faster and grow up very early because my parents were never there for me. I feel like I am ready to be married, and I want to take that next step, but all I hear from my family is that I am too young, and I am a sophomore in college, so I will be missing out according to them. It is very discouraging, and I don't know how to deal with them. It makes me worried amd stressed. Any advice?