If you are giving him Sub Q I wouldn't bother feeding him right now I would make sure his temp is not dropping. If you feed him and his temp is down it won't digest and if he is not suckling/swallowing you may aspirate him.
I am sorry your baby is having problems again.
Pups need fluid/warmth and glucose. The Sub Q can sustain him for a bit without doing the feedings until you get him stabilized.
You can get the gas drops for infants at Walmart.
They do help if it is indeed gas. Also if he has not had BMs you can use a sliver of a suppository just hold it in his rectum a bit and it will help him to go.
Wishing you the best, sorry I wasn't on earlier my son had surgery this morning
Deana
Prestigeous Yorkies