Please help

They said itd get better after a week then a month then for sure three months but here we are past three months and its worse than ever. Its got me cryingg and feeling so helpless. Heres whats going on with my baby

--gags often

--chokes on milk

--stomach makes uncomfortable noises a lot

--vomit (1-6 handfuls)

--cries during or after eating

--latches unlatch latch unlatch

--eats for 2-5 minutes, unlatches, then wants to eat again after 10 minutes

--falls asleep eating then wakes up 5-10 mins later wanting to eat again

Does anyone have an idea whats going on???? Hes breastmilk only born at a healthy 8.5 lbs. the only problem we had in the beginning is my production but now all of this