early wedding 😳

First off, I'm 18 years old and my man is 22. Ive know him almost a year and I love him more than anything.
He's from a country over seas so the culture there is much different than the US. Early on in the relationship he brought up marriage and it made me feel nervous.
I knew I eventually would want to marry him but not so soon. Well, for reasons I can not explain on here, he's been pressuring marriage on me and I need to marry him or else he has to leave the country. I've thought about it in private and I've decided I would marry him. (Although I'm scared what my family would think) what're your thoughts on marriage for an 18 year old