Sorry you're having issues :(
Does his poo look yellowish, or is it more green smelly/foamy? That's one indication of if there are digestive issues as well.
We have issues with our son - he'd be unsettled after feeds and need to be held upright - often screaming for an hour until his stomach emptied and he'd go to sleep, then an hour later we'd start the cycle again. For us, I had to eliminate all dairy from my diet (every trace - it's surprising what food products contain dairy, even a lot of margarines!). We also had to put him on Losec as well for his reflux. After making the changes to my diet, we finally got that mustard-seed poo everyone talks about (about 1 mth before he started on solids, so didn't get to enjoy the non-stinky poo for long).
For us, gripe water and infacol did absolutely nothing, so you're not alone!
If you do look at formula feeding, you might end up needing a special formulation which is allergy friendly - not sure how to get these, but I used to know someone who couldn't use any off the shelf products as had a worse result than with breastfeeding, but found the special formulation to be a life saver!