What should i do?

I am 19 years old and me and my boyfriend are the same age. We both are in college. This is his second year and this will be my first year. He asked me to marry him about a week ago. I said yes! He has been talking about children and wants to have some after we get out of college. This will be his last year in college and next year 2017-2018 is my last year of college. It's only a 2 year course we are taken. I want to have a baby and he does too I just don't know if we should wait until serval years after marriage or couple months after. What should I do?