12 Week Scan (NT Scan)

I go for my 12 week scan on Monday (Australian time) and I'll be 12+4 weeks for it. I'm just wondering if it's normal to feel worried/anxious about the scan? I haven't seen my baby since my 6 week dating scan and I'm worried the baby hasn't grown since then or it's grown but it won't have a heartbeat. Has anyone had the same fears leading up to their scan and everything be fine?