I have functional dyspepsia (or non ulcer dyspepsia) read up on it, you may have that! its a stomach disorder and docs sometimes diagnose it when all the other tests they perform come out clear! i have had it for years!! i get stomach ache and nausea at times! but someone else i know who has it is sick after everything she eats, that can be because the stomachs motility (the way you digest your food) has slowed down so the natural rythm in which food is digested is a bit out of tune!
The anxiety you are getting is normal i got a load of anxiety from this condition, you are bound to if you feel unwell alot its natural, i have a few things which you should do...
Exercise!! alot its great for feeling good and lifting the mood
Drink herbal teas, they take some getting used to but are good for stomach aches! try chamomile, peppermint and ginger.
Also take digestive enzymes with your food, and eat little and often. You should try shakes if you cant eat! drink plenty they will give you energy and help put weight back on.
For anxiety take something called 5htp, read up on it write ''5htp anxiety'' in a search engine you will get good results!!
Take it with a vitamin B complex. And a multivitamin as your diet isnt too good.
Also practice relaxation exercises!! buy some CDs and listen to them (on ebay they are cheap)
I think you may notice a good change!!