Should I take things slow?

I’m 22 yrs an he is 26 yrs, he has a baby boy (1yr Old), we have been together since 2011 and the baby was already on the way. We took things as casual (as I was a virgin) so I didn’t mind any events happening in his life, we became so close that every weekend we would be together, he took care of me financially and all (the babby mama stays far), so things got really bad when the babby mama find out, he called me denying me in front of her, I was hurt but not much, so I decided to let go but he came back apologised and i forgave him and that was before June 2012, so since then we have been ok, December he broke my virginity and has promising to pay damages in July and also start lobola negotiations,,, but my problem is we never talk about the babby mama, and I want know should I agree to marry this guy or should i take things slow or what?

Confused gal