You won't like this...but you MUST eat more! And I'm saying that as someone who successfully lost 80 pounds and who has kept it off for several years. Any diet that restricts your calories to 1200 will fail, even if you didn't have celiac disease (I'll tell you why this complicates things later). It's not a maintainable amount to eat, because you will not get enough vitamins, minerals, and energy from it.
The absolute minimum daily caloric count is 1300 for a diet. 1300 is not a maintainable number for long term weight maintenance (1800 is.) Also, never keep the same daily caloric intake. If you keep a consistent number like 1300, your body will adjust to that number. It will conserve energy and lower your metabolism until that number is sufficient, which means you'll never lose the weight. Instead, vary your calorie intake daily (say, 1300 one day, 1500 the next, 1800 the next.) Don't be afraid to occasionally go over 1800, even when trying to lose weight. It will make the adjustment to weight maintenance much easier, and will prevent you from gaining the weight back when you go off the diet. For weight loss, an ideal average caloric intake over a week is around 1500-1600/day (I'm assuming you're of average build; otherwise the number will vary accordingly.)
Now, that said, right now you should not be dieting. Dieting is a shock to the system, and you've already received a shock by having celiac disease. Your body is in starvation mode due to loss of absorption over the years, and dieting will prolong this and make it more difficult to recover. Starvation mode is also counter-productive to weight loss--it will make any weight loss much more difficult to achieve, or even impossible. Your body needs healing right now. You will have temporary weight gain, but this is absolutely okay. Once your body feels like it's healing, your weight will even out, then you can work on losing any unnecessary weight.
One other thing: you should absolutely get your thyroid and vitamin levels checked. The weight on the stomach is likely bloating, but the back and arms is more indicative of thyroid trouble.
Also, be very careful with what you're eating. You can't assume anything is safe. A product from one brand (like Worchester Sauce) might be okay. From another brand, it might contain wheat. For a third, it might be cross-contaminated in factory. You literally have to check every single product you buy, from any different brand, to make sure that a) it contains no gluten, and it wasn't processed on any shared lines with gluten. Otherwise, you'll delay healing.
Thank you! I have eliminated dairy and pretty much all processed foods since I originally posted this because I KNOW something is not right, I am just not sure what it is.
I am going to get my vitamin levels tested in a little bit and am going to be seeing my gastro in a few weeks as well.