I have my second ultrasound tomorrow and I am exactly the same as you. As pp said try to think positive, I know its hard but I think it does help. My last ultrasound was 6 weeks ago and I was soooo looking forward for this one, but now, I am really scared. I have a bit of morning sickness but otherwise, I havent put on any weight and havent got a "belly" as yet either. So my mind starts the "what ifs". I think it is natural to worry. Try to keep busy and before you know it will be Monday and you will see your little one.