This is exactly how I am. One time I can eat something fine, and another time, same food, and it just comes right back up. What is strange is that I almost never do this all day when I am at work . . . It isn't throwing up in any sense - just PBing. Sometimes if I wait a while, I can continue eating, and sometimes no matter how many times I try and finish eating, it just keeps coming back up! It isn't painful, and doesn't seem to be harming me, as this has been going on (off and on) for months, and isn't affecting my band (thank goodness!)