I'm guessing that too, although maybe the door let wind it, which blew the hood off, and landed in a bathtub full of primer.
What you're doing with a bathtub full of primer I'll never understand though.
That sucks man. Reminds me of when I got my door hinges reconditioned. The driver's fender wasn't lined up right, so I opened the door a couple of days later, and crunch, bent the fender and broke off a large chunk of cleared metallic silver. It was about that time I went upstairs to get the shotgun.
I forgot to latch mine on the 65. I was only going 30 MPH (thank GOD) when it flew up. It didn't do anything to any other part of the car except the hood.
Needless to say, I now have a new hood. I really like the look of the stock hood in the black color that they ship it in. It has the holes for the F O R D . I have since put hood pins in, and am making it look like a vintage Trans Am car (with graphics and stuff).