need some advice! :( I had a bed side scan with my dick head ob today. Baby's head is measuring at…

need some advice! :(

I had a bed side scan with my dick head ob today. Baby's head is measuring at 30 weeks (2 weeks ahead) but his belly is measuring 25+3. My ob told me all was fine but my gut is telling me something is wrong. His heart sounded a little slower then normal so I'm a bit unsure what to do. I want to go to the hospital to see if he is alright but I'm worried they will tell me I'm just being stupid :( any advice or help?