Today I needed to sleep post-appointment so that I could get back to myself...
...but here's the update: my uterine lining looked perfect - "triple stripes," which apparently is what you want a baby to implant into.
Oddly, neither follicle had grown since yesterday - still 15.8 and 12.4mm. So, I'm praying that that just meant the eggs inside were maturing rather than wasting energy on simply growing. Or maybe they just took a break because of the yucky weather yesterday and didn't want to work so much.
I appreciate all of your prayers. I know God is hearing them and letting us give this whole pregnancy thing the best chance it's got!