Hi everyone - and congrats to you all!

I am expecting my second child mid October after a 13 year break from it all. With this pregnancy I really worry that something could be wrong - I don't know what but just worry. It's not a constant worry it just comes over me every now and then and I get worked up and anxious. I have had a detailed scan and my doctor reassured me that the baby is fine. I read somewhere that maternal instincts are never wrong, does anyone else worry about their baby? Is this normal? I can't even remember if I worried with my 13 year old daughter.