Nervous...

We are coming up to our second ultrasound, the big reveal! I have been looking forward to this for months now but especially this past month since I scheduled the appointment. I feel like ive been waiting for Christmas. It seems like all of a sudden a couple days ago I got SO nervous that something is going to be wrong and now I cant seem to stop thinking it and what if. I know its important not to stress and to be positive and Im trying but Im just so scared. Anyone else felt this way? All I can do is wait to see but I hate that Im feeling this way...