It's been a couple months since you posted but I figured I would still give my advice. I am also 21 and I told my family about getting engaged. I asked my mom if she thought I was too young and her response to me was "If you feel like you're ready then no, I don't think you are too young." I think that if you have thought about this from every angle and you are 100% sure this is the guy for you then make that leap and don't look back. Just make sure you two talk about important topics before you get married, and this would go to anyone considering getting married. Talk about how you will raise your children, religion, money, house duties, in-laws, values. I have been best friends with my boyfriend for over 8 years and we only started dating 4 years ago, but we still want to make sure we are prepared for marriage. We bought a book by Monica Mendez Leahy titled 1001 Questions to ask Before You Get Married. I would highly reccomend this book to anyone, it is a good way to get to know your partner better and you may discover things you didn't know.