At least you hadn't made anything out of the fabric. My Jack peed on a queen size top that I had laying out on the floor ready to be pin basted. I had the backing down, the batting down and the top on top. I was trying to get supper started and he let me know he wanted to go out, but I had to do something else. In the meantime, he decided to go on the quilt. I was able to just spray the bottom two layers, but had to launder the top before I could pin baste it and quilt it. I never told my sister-in-law to be (that's who the quilt was made for) what had happened. I was hoarse for 2 days from yelling at him. I was so mad that I know I couldn't touch him, so I just yelled.
Good luck getting it out.