I took off my shoes, changed into sweatpants and a T-Shirt and started to climb into bed. And was stopped cold. By pee. Cat pee. Under the covers. I pulled the covers down and lo and behold, poop too! Hooray!
I was really pissed at Copper, until I remembered the yowling and looked in the kitchen. her box is in the mud room off the kitchen. The door was shut and she couldn't get to her box. There's a cat flap in the door, but if it is dark, she isn't used to such things and wouldn't have thought to use it.
So I stripped the bed, blotted and Frebreezed the mattress (repeatedly) and took all the linens and comforters to the laundromat. Thank goodness I tried to take a nap or I wouldn't have found out until well after the laundromat had closed. Fortunately, being at the laundromat let me calm down so I wouldn't yell at Copper any more. It wasn't her fault, though I wish she'd done it somewhere other than the bed.
Everything seems ok now. I'm going to get a urine-smell-remover at the pet store today. I'm also going to check the bed as soon as I get home to make sure this was a one time thing.