Kind of scared...any help appreciated

Re-posting from the main VSG page...

I originally had VSG in August 2009.  Starting shortly after the surgery, I experienced occasional heartburn which got increasingly frequent and terrible to the point I had daily heartburn which wasn't responding to antacids.  Now fours years later, and several visits with a different surgeon, he determined (through scans) that there was at minimum an extra portion at the top of my stomach where acid was collecting and then, going back up my esophagus leading to the heartburn.  He thought a second procedure would help seal that off and give me a better quality of life.  

I just got home from the hospital this yesterday (Tuesday 4/1) after having, essentially a second VSG procedure...which is pretty miserable.  I guess from what the doc said, my stomach hadn't really been sealed that well the first time around, and that a portion of the original stomach was still there creating an extra pouch, which was the reason for the repeated heartburn I was having.  I also had developed a hiatal hernia.  I originally lost 60 lbs or so back in 2009 and 2010 but slowly started gaining it back.  However, I'm as active as I've ever been and so, scale notwithstanding, I feel and am pretty healthy (no significant meds, no heart issues, no diabetes, no sleep apnea etc).  It turns out that with my level of physical exercise in the last two years or so sometimes I wasn't eating ENOUGH calories to burn and hence lose weight (which I figured out after meeting with a Registered Dietitian and reviewing my diet).   

I know the surgeon now was focused on getting me to be able to lose a little more afterwards, but I think he believed that I had gone back to eating too much because of the size of the stomach/the extra space that was there which shouldn't have been. Maybe I should have been more specific, which I'm now regretting, although I did tell him I was pretty active.

When I asked him how big my stomach was now, he said the size of his thumb.  I am already freaking out about having to figure out how to eat all over again; and now, how in the world I'm going to be able to eat enough with such a tiny stomach for an active lifestyle OR if it will stretch a little.  I think it was originally larger than some peoples but the original surgeon factored in my age, lifestyle etc.

Ok, please tell me that its possible to eat enough for such an active lifestyle and what you all recommend or tips on how to get enough protein in with a stomach the size of a thimble...kind of regretting doing this at all at this point....   Thanks!