Our second ultrasound was this morning, and had good news. The 6w1d grain of rice is now a 7w4d peanut (as you'd hope 10 days later) with a strong heartbeat. I don't think I realized how anxious I was because I got back into my car afterwards and lost it. Like happy tears, but still some ugly crying.

Thanks everyone for the good luck wishes.
Re: Update: Happy baby