Hey Janet,
Absolutely not. You are not posting too much at all. I apologize that not all of your posts get responded too quickly enough. I have been a bit distracted with the office and have not quite been able to hit the forum with the frequency that I need.
Anyway, your compositions are very nice and your subject is excellent. The first shot has some problems because the floods are burning out the crested's hair on top of his head. Also, unfortunately, he really needs a brushing as you lose much of his face behind the hair.
The second shot is much better. Not only is the lighting better balanced (though there is a tendency towards hot), but the pose is not causing you to lose his face. Very well done.
The last shot is very good - not my particular cup of tea with the pose, but honestly, not at all poorly executed. The one thing I will say about the 1st and 3rd shot is that as you go further down your dog's body, they seem to get richer in their pinkness. I am not sure if this is a result of under-exposure or if it is how they are naturally.
James