Not ready for marriage

My boyfriend & i have been together (officially) for 3 years. we have an 8 month old together. we've known eachother about 7 years (we met my freshman year in highschool) Im 21, hes 22. Im not sure why hes so ready for marriage but im not. everytime the topic comes up we end up arguing. he got in some trouble back in high school& has charges that will effect me if we get married right now. i see myself being with this man forever. thats my high school sweetheart. but i also have some things i would like to fix before i get married (debts & credit mostly) i told him i wanted to be engaged for atleast 2-3 years before so that will give me a little time to pay some stuff off. but nope. he thinks that i think a ring defines what we are. which it doesnt. a ring doesnt mean anything to me honestly. idk what to dooooo. he gives me headaches when we argue about something so silly.