6 wk old baby only sleeps in arms

Cindy
Hey all. My little baby boy doesn't sleep well by himself during the day and night. He screams when he's on a flat surface so we constantly have him sleep on an incline. Even then he would wake up 30 minutes to an hour and I would have to rock him back to sleep. I give him Zantac, swaddle him, burp him in between ounces, and hold him upright for at least 30 minutes. He arches his back, swings his head from side to side, and kicks his feet which causes him to wake up. I give him half formula and breastmilk since every feeding. 
So question is, how come he can't sleep for more than 30-60 minutes by himself? Is this all normal reflux? Thanks!