First ultrasound- low amniotic fluid?

Hey everyone- I had my first ultrasound yesterday, we saw the heartbeat, Dr says measuring 6w3days, only about a week less than estimated. He said that there was very little fluid around the baby and that was definitely not normal. He said it could be from dehydration (My appt was at 11am and I'd only had a bottle of water on the way) and/or there's a high possibility of miscarriage. I've not had any bleeding or spotting, but also not many pregnancy symptoms aside from fatigue and mildly tender breasts. Has anyone ever experienced low fluid in the first trimester?? I've already prepared for the worst, but can't help still having hope.