Hope my boss(es) don't read this

I didn't realize my slow decline at work until last Monday. Monday we had a meeting and two hours later I was emailed a ton of materials that one person just whipped up. That used to be me. I used to get back from a meeting and crank out deliverables and prototypes. What happened?

My current excuse: I'm working on six different projects simultaneously, 3 have a hard 12/1 deadline (really 11/26 with the holiday), and I change between them 20 times a day.