My 4 month old westie is pooping blood and he keeps gagging when he coughs. I don't know what is wrong and the vet is closed. HELP!!

Could be a lot of things. He may make it until Monday, but you will feel better if you do manage to find a vet. Start with your vet's regular number if he doesn't have an after hours one. My vet's number forwards to a paging service. Had to call a couple of times over the years, but didn't have to take the puppy in.

If that doesn't work, try Petco and Petsmart. Their vets keep longer hours although maybe not Saturday evening. If not, many cities have a 24 hour vet clinic. If none of that works, you will feel better for trying.

If the pooping turns to diarrhea, minutes count. Do what ever you have to to get him to a vet.

Hi,
You posted this Yesterday, March 4. I do hope that if you couldn't get in contact with your Vet, that you kept calling any Vet, trying to find one.
I do wish you the best, and hope this works out OK.