You did the right thing. We had to put our dog ****ear down a few months ago, @ 13 she was going downhill fast. Loss of appetite, incontinence, and trouble getting herself up and walking from bad hips and arthritis. I was trying to convince the wife it was time but she was stubborn and holding on. Unfortunately we witnessed her have a horrible seizure one evening, I had to drag my hysterical wife out of the room and thought the dog was dying. She recovered but we knew it was time now and she was not going through that again, our vet came to the house and put her down the next morning, it's like losing a best friend or family member.
I'm sorry for your loss, nothing but time can sooth the sorrow.