What's going on with my dog's health?

My dog is 2 years old. If he is ill would the other dogs be ill? My boyfriends dog is a 6yr old pit and her puppy is 8 weeks. He acts his norm outside and still wants to play but when he comes in he is blah. He don't want to eat and if he does it is very very little.. After being inside for a while you can just feel heat coming from his body. He always has goop in his eyes.. When he coughed the other night all night I gave him benadryl. My vet uses it for allergies so I gave him one.. Well any advice you can give me is greatly apprciated very much.. I added you to my friends list so if I have any questions I can email you.. Is there any certain signs to look for in heart worm? His cough is pretty much gone but still there.. Thanks

Hi,

Coughing and watery eyes can be an allergy, so Benadryl will likely help. However, I do think you should take your pup into a vet ASAP for a checkup -- anytime a dog does not eat, it needs medical attention.

Coughing IS also a sign of heartworm:
Heartworm symptoms in the dog can take years to show up. It usually starts of as a mild cough which most owners dismiss as unimportant but then gradually worsens to include symptoms like fatigue, more severe coughing and breathing difficulties. If left untreated, it will result in the eventual death of the animal. The more heartworms there are in the system the more severe the heartworm symptoms are. If the liver is involved, then other symptoms will include jaundice, loss of appetite and collapse.

IF YOU AREN'T GIVING HEARTWORM PILLS, START NOW. And take your pup to the vet!