Bexster, you could be describing my situation right down to the dummy and the move! (We moved 2 months before DS was born and still haven't unpacked!)
We have all the same symptoms with DS and assumed it was wind, but infacol didn't stop the evening screaming. Nor did colocynth crystals or colief.
Our HV thinks he has reflux and we were prescribed infant gaviscon. Initially, I didn't use it properly - only gave it to him when he seemed to need it. HV says it needs to be given before every feed, the box says up to 6 doses a day. DS is exclusively BF, so can feed up to 9 times a day, so we're skipping the middle of the night feeds when I can't face trekking to the kitchen he is at his most settled. Yesterday he had gaviscon all day.
He has been much improved today. Napped for two hours in Moses basket (propped like yours). The longest day nap before this was 37mins. He also sat in my lap for a long time this morning, then lay on his playmat, without crying.
(Thing is, he also had his immunisations yesterday so I'm not yet convinced it's purely gaviscon having an effect.)
What has happened is the weirdest nappy I've seen on a BF baby (DD was BF until 15 months). So odd I took a picture to ask HV. Is there a way to share images for comment from experts on here? Reading this, I'm concerned it is constipation. How do I manage that with a BF baby?
Does your baby have lots of salivary bubbles, sometimes drool clear liquid, or vomit clear liquid with cheese-curd white bits in it? I was told the bubbles and drool were an indication of wanting to be sick, and the curd-like posseting suggested the milk was partially digested before coming back up. Therefore ... reflux.
On the dummy ... We were advised to try this as well but DS refused. FWIW, our dentist told us dummies are not great (DD had one which is why I was trying to avoid one with DS), but said if she sucked her thumb to give the dummy straight back because thumbs are worse.