I can see that it is easier to read lighter colors, i.e reds, Otis is a very dark brindle, so unless you stand over him, you can hardly see his wrinkles/expression..
Well last night was good. My daughter wasn't feeling to well so I went to lay with her on her bed and our B came with us. When it was time to get off the bed, my daughter took him down and he did not show any aggresive behavior and when it was time to exit the room he didn't growl or anything. This is a good step though I still haven't been able to stop the nipping but hey it's still good!
I think you should go back to your vets especially as this has been happenig ever since the emergency surgery. It could just be coincidence I suppose, but if she were mine I'd want to check. As Pat says more information is needed before suggestions can be given.