Baby 3 days behind..

Melanie • Im 27, mother to 1. Spinal cord tumor survivor still fighting i used to be paralyzed had three back surgeries.

So my first obgyn appointment was 10/18. She said baby measuring 3 days ish behind. I should’ve been 9 weeks baby was 8 weeks 3 days. And I didn’t have a period in July to know my cycle days.

When we was leaving she said you guys are 9 weeks today! BPM was 172

Sooo which one do I go with?!