I was in the shower when it happened,  so I didn'thear anything.  Apparently,  my puppy (8 months, adopted at 6 months) chewed my boyfriend's son's very expensive shoe.  I immediately offered to buy a new pair, as I obviously felt terrible.  When I went to see my dog, who was now in his crate, I noticed a wound on his front leg that was not there earlier.  I asked my boyfriend what happened, and he said that my dog went to his crate on his own, and he didn't touch him.  I want to believe him, but I've seen him get very angry toward my other dog in the past, and had to intervene before he hurt her.  

Now my boyfriend is upset saying that I had no right to accuse him of hurting an animal.  Am I the asshole for thinking he could have caused my dog's injury?