I sometimes have trouble changing my profile picture too; it tells me my changes have been saved but then I select Return to your profile and it's the old photo. I'll try a few times and then wait a day or so and eventually it works.
Love that photo of your pups! My sister and her husband just lost one of their English Mastiffs, she had cancer and other health issues and was almost 11 years old which is old for a giant breed. Their male is almost 10 and he's still doing great.