Sorry, that wasn't very helpful of me was it?! I think you're normal, being scared of kids before you have any, but when you start thinking of trying for a family you'll be scared you won't be able to have any. With one on the way, you'll be scared of pregnancy and complications, then scared of childbirth. When little one is here, you'll be scared you're doing things wrong, then scared of leaving them at nursery, scared that they'll get hurt when you're not with them at school, or that they'll fall in with a bad crowd, or that they'll elope and never visit when you're old.
The list is endless - the short answer is no, you're not strange at all!! It's always scary, but it's totally fantastic and you'll never regret having children, ever. :o)