Got drunk at a party... Weird thing happened?

I was at a friends college party where everyone was drinking a lot. I ended up taking several shots of grey goose vodka, and drank maybe 3 or 4 bottles of corona. I remember laying down on the couch and then I ped out. I woke up several hours later face first on the couch and my pants and panties down at my ankles. My inner thighs hurt terribly when I woke up and I could barely walk. My friend who was throwing the party told me that it could have possibly been his dog because he has a tendancy to hump things. I'm so afraid that this dog had gotten to me! How can I get the thought of the dog out of my head! My life is ruined!