Firmly in the groove now. I can tell because I kept waking up in the night with ideas about the love story thread. I don't know if any of them will make it to the manuscript, but just in case I was afraid to go back to sleep and risk forgetting in the morning.
So, at about four a.m., I grabbed an extra yellow thank you card envelope and red pen from my desk to take back with me to the nightstand.
I have no idea why I hadn't been prepared in the first place, but I sort of forgot what it's like once you're really sucked in. Ideas just hit and you have to do something with them, if only as a precaution.
This morning, I copied them back over onto the notepad I'm keeping in the manuscript folder, and really, there's some potential there, including a logical explanation for a key character scene that otherwise would've had to have been cut entirely as part of the plot re-focus. Encouraging.