Hello, Im 37 starting protein shakes and protien juices as a supplement to diet. I have tried numerous name brands lactose free, gluten free, surgar free. Six star, unjury, eas, muscle milk, isopure, nectar, beverly international, criosport. Everytime no matter what I try i get ver bad chest pain and tightening of my chest and throat. I really need this diet to work becuase I will be having surgery soon and this is crucial to my success before and after surgery. Any suggestion why this is happening or any suggestion of what can work?