Thought I'd follow up on my post below about whether POAS at 11dpiui is too soon. I went ahead and pressed for the beta this morning, at 12dpiui. Confirmed BFN.
RE proposes another stim IUI cycle, but maybe bump it up a little this time, as we did a very low amount last time, but wants to see a baseline u/s to see what we have to work with this next cycle.
Thanks for all your helpful comments below! At least I know it wasn't another chemical, still so upsetting though.