I'm sorry as I have only just seen your post. Your dog needs urgent attention. I suppose by now (3 days ago since you posted) you may already have taken him to the vet. But I hope he is okay?
My pitbull has been coughing a lot and usually it's dry and kind of gags but nothing comes out and up until today she just started throwing up blood I have no idea what it is
Please go to your vet, your dog could have chewed something up, plastic, socks, shoes, bones, poison, and its cut in his mouth, esophogus, stomach....
You really need to contact your vet or a vet of choice...I would not let this go w/out knowing how serious or not...
Pitts are known for chewing and getting into trouble like this..
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