I know it’s a small thing considered that you’ve banged out a lovely story and are eager to pitch it about to agents and editors, but, please, for the love of all that’s holy, keep a list of those you query/submit. I keep getting a sense of déjà vu when I open a query that sounds strangely familiar. A quick check of my files invariably shows that this is, indeed, a boomerang query, and I have to turn around and reject it a second time.
Odd that I can spend hours trying to remember where I parked my car, yet I can remember submissions from five years ago. Must be a blip in my DNA.