I definitely feel you about projecting query anxiety onto other things. At first all my anxiety was channeled into OVER-researching agents and subsequently revising my queries to them 8000 times, but I've moved on to personalize, submit, and walk away. Then doing as you say - projecting.
I'm working on a few flash fiction pieces to get some of my shorter ideas out so they'll stop bugging me. I'm hoping once I get those done, there will be room in my brain for the bigger ideas to more fully develop. I have rough ideas for two more novels and a fleshed out idea for a third, but the fleshed-out one is so
serious... not sure I feel like writing something heavy right now.
Here's hoping you have some inbox love from agents today!