Young marriage?

So I’m 19 and my boyfriend is 23. Both of us are in the Army and are stationed at the same base. We’ve been together 7 months and he wants to get married. My mom doesn’t support us getting married so soon and I don’t have a problem with marriage, I just want to wait since I’m young and we haven’t been together for too long. He’s getting ready to get out of the Army next year and he just wants us to be together all the time and get the benefits married couples get. We had a conversation about it and I told him I don’t want to get married just for benefits and he understands but he doesn’t want to wait since we both know that we want to stay together. At some point in the discussion he even said “if i have to wait years or months to get married what’s the point of being together.” After he said that I stopped talking to him for awhile and he apologized and said he’s just scared that I won’t feel the same for him within a year or so... I just don’t know what to do anymore.