My 13 year old chihuahua/ pug has been doing a hacking sound for a month now. Sometimes its at night sometimes after a bark sometimes just randomly. Its not constant. I took her to the vet he said all seem well and sent me home with temaril p unfortunately i stopped giving it after first dose due to some diarrea and nausea. Does anyone have an idea what it can be? I am terrified its heart related. She was licking floor alot before this and has also reversed sneeze.