My baby is so crabby

My son is 16.5 weeks old. He is very, very crabby lately. I mean to be honest, he’s a pretty crabby baby in general. Very hard to make happy. He was born 3 weeks early, so I don’t know how that affects his “leaps” of anything. He has bad acid reflux and spits up multiple times after every feeding. He burps these juicy disgusting burps and gets deep, painful sounding hiccups very often. He also has terrible gas that just doesn’t get better, despite gas drops, me changing my diet, etc. He spends most of the day straining and groaning and trying to poop even though he goes 1-2 daily and it’s liquidy breastmilk poop (I exclusively pump). He doesn’t nap great, but he’s trying to sleep better at night, though his sleep is never calm, he’s very restless, and he fights sleep before he goes down. Now he wants to be held and walked around all day long. If you put him on his belly, he screams. If you put him on his back, he tries to sit up (which he can’t, because he can’t hold up his head great because he refuses tummy time), pulls himself up on his elbows and lifts his head, and then screams. I’m starting to think he just doesn’t like me. I know that sounds stupid but that’s honestly how I feel. I’m supposed to be the one to make things better and I have no idea what to do for him.