LR I had a similar problem with my DD when she was tiny. She basically wanted to suck all the time but her body couldn't cope with the quantity of milk she was getting. Result - much screaming, explosive poos and a baby who looked hungry but feeding made it worse. I tried to make sure I waited at least 2-3 hours between feeds to make sure she had digested the last one and reluctantly I did resort to a dummy. I didn't want to but it was the only way she could suck and not receive milk. DD did not have reflux or other physical issues so in her case it was just a matter of too much milk for a tiny little body.
HTH and good luck!