I am a only child and now a mum of three daughters

Not quite the same, I was one of three, I have two sisters.
Went on the hand two children myself a son and a daughter, two was enough.

I am an only child raised by my mother but am now a single father raising my wonderful daughter

You are still young, you will decide when the time comes and who you are with
One step at a time

Yeah i think it's normal

Why would it have to be a "big" family? One child and one partner is still a family. Heck, on parent and one child is still a family.