Apologies if there are similar posts out there.
I am 39 years old and have a 1yr old DS. He is our world. DD is 42. It took me a while, and an operation to fall pregnant and I hated every minute of pregnancy. Labour was long but ok. My issue is that DD doesn't want a 2nd baby but will have one if I insist! And me? I have no idea what I want. 
It is only now that I am starting to feel more human again and the prospect of falling pregnant right now fills me with dread.
I don't have a great relationship with my brother. All my friends with 2 or more kids say they always knew they wanted more.
I am terrified that if we have a second child we will struggle (DH is very hands off) but if I don't - DS will be lonely etc. etc.
I feel that my age is putting me under pressure to decide. I know I could still have a baby at 43 but this isn't really what I want. How can I go with my gut instinct when I don't really have one?!
So my question is - how did you know you only wanted 1 child (or more than 1?)