Sis, unang una, pareho ba kayo ng end goal for entering into this relationship? Pareho ba kayo marriage ang gustong hantungan? Kasi there are people na they just want someone to be intimate with.
It seems like sayo, yun ang end goal mo. Pero sa kanya pwedeng (1) marriage ang end goal nya, or (2) wait-and-see sya tipong kung makita eh di good, kung hindi ayos lang, but kung wala pa enjoy lang muna sya, or (3) gusto lang nya to have someone to be intimate with without marriage/live-in in mind.
If both of you are on (1) and (2), since matured na yung age niyo, I would take it that you are gauging each other as potential lifetime partners. But since matured na nga yung age niyo at may biological time limit (you want to have a kid pa), you can't wait forever. You also need to know if he feels the same way too or if he's just stringing you along if he realized na hindi pa ikaw.
So I suggest put a time limit kung hanggang kelan ka mag-eenjoy the moment. Kung 21 y/o ka, pwede ka pag maghintay hanggang 10 years. But with your goal in mind, hindi ito pwede. Now it's up to you kung kelan ka mag-dederecho or mag-bibigay ng hints about marriage or future plans. Pwedeng after a year or two. Pero maganda kasi, by that time, nararamdaman mo na rin sana na "ikaw na" without guessing.
Meron nga akong kilala (not personally though) late 30's na rin, bago pa lang magstart ng dating dinerecho na ni babae si lalaki, saying something like, "if you're not doing this to be married eventually, then I don't want to waste my time." In the end, nagkatuluyan naman sila. What's important was they were both on the same page from the beginning.
On the other hand, how can you be sure that he's the one for you after just 5 months of dating? Did he meet your criteria na ba of a lifetime partner (e.g., respectful, kind, financially stable). Being matured, mas mahigpit nga ang criteria compared sa younger and inexperienced ones. You don't need to answer here.
In the end, I think you need to strike some balance. Hindi nagmamadali pero hindi rin magpapatagal.