New Years resolution help

I need help. My son is 15 weeks old. He has terrible gas and acid reflux that is not being treated by a doctor. He screams and cries a lot from gas pain, strains to poop nearly all day even though he goes 2-3 times per day and it’s mushy or liquid. He spits up after nearly every meal. He is fed breast milk in a bottle because I have oversupply and over active let down and it made the reflux worse. I am trying to eliminate dairy from my diet and see if it helps with the gas. He was born at 36w6d and was 5lbs12oz but he’s now about 14 pounds. He eats practically every 2 hours.

Anyway, my resolution is to get him on a better schedule. He sleeps terribly—tosses and turns and kicks and moans and groans all night, which I assume is due to the reflux and gas, because laying on his back sucks for him. He sleeps in a pack n play. He will really only nap for like 30 minutes maximum unless I’m holding him. He seems exhausted during the day because he doesn’t sleep well at night. He doesn’t want to go down until 11pm and will then sometimes sleep til 3 or on days when he’s really tired, he’ll sleep til 5 or 6. But this is only recently, and we’re coming up on the 4 month mark so I’m worried about sleep regression. After he eats, he has to be burped and then kept upright for 20-30 minutes because of the reflux. Everything I read says it’s hard to get a reflux baby on a schedule but I will be going back to work eventually and I need to provide him with some structure so that he can function better and so can I. Can anyone share their schedule or any resources that would help me figure out one for us? Thanks!