My Pediatrician told me to give my son 2-3 ounces because he has a?

problem with reflux and he is on Zantac. She said that he was gaining a lot of grams during the day that is out of her range that she likes. I do respect her, she is a great pediatrician. However, when I go to burp him during and after he eats he still cries. I WAS feeding him 4 ounces every 3-4 hours, and now he is a 3 ounces. But he cries some after I feed him. Since I have had him I have NEVER seen him stop eating because he is full. I feel he could eat until he explodes! Does he just wanna suck on something? He will cry all the way up until I give him the pacifier, and then he will still cry and I have to rock him and "Shh" him to calm him down and that takes a while. Any thoughts?