I haven't read all replies so apologies if this has been said already.
Firstly, it won't be to do with breastfeeding. I must have at least 5 friends now who've been in a similar position and nothing at all has changed when they've switched to a bottle - if anything it's been worse and have them felt really sad that their breast feeding journey ended early, so unless you want to stop breastfeeding, don't do so as likely nothing will change!
That said, it might be worth looking at symptoms of lactose intolerance in babies and seeing if baby has any of those. If yes, a visit to the GP/HV is in order. Especially as you say baby is gassy.
Cranial osteopathy might be a good idea too? Many babies who are "cryers" are much better after seeing a cranial osteopath.
Have you tried white noise/brown noise/womb sounds?
Was baby born very quickly? Could they have fluid on their lungs that they need to get up? (This was the case with my eldest!)
Are they being burped sufficiently and upright for at least 20 minutes before being laid down?
Have you tried swaddling? This worked wonders for us with our youngest and also helps with gas issues!!
Have you got a sling? That way baby is upright and can go to sleep in the daytime to stop them getting overtired at night.
Instead of infacol or gripe water, I'd recommend sugar water instead. Much more effective.
Also if it's stomach cramps, have you tried eating prunes if you're breastfeeding? Can really get things moving!!
It would be worth joining this Facebook group - I've found it invaluable and Sarah who runs the group is a baby expert! She's a maternity nurse and baby consultant and really knows her stuff.
www.facebook.com/groups/brilliantbabysolutions/permalink/526305602918254/
Sorry for such an influx and you don't have to reply to everything but just some thoughts for you