Help I need some advice....

My OH and I have been together a while now and we are sadly no longer young... Times ticking with our body clocks.... We had planned to begin with TTC in the next month but I have a reservation... We are not married and I do not feel right about it. I'm not Muslim, he is and I have a son from a previous relationship. We can't afford a big wedding but could potentially have a nikah instead which I'd feel happier doing. Its not a legal wedding here in the UK but at least its right in the eyes of god / Allah.

How to I approach this subject without scaring him off? We are serious about being together and are in it for the long haul. And yes, I know sex before marriage is haraam but not everyone is perfect (the OHs words, not mine).

I'm so confused as I want to TTC but its just not sitting right with me.... I always hoped I'd be married before kids but plans go wrong some times!.....

Thank you ladies x