Hi - I was diagnosed with coeliac disease in November and was just thinking yesterday that I'm over the worst of it, acceptance-wise and it really is OK..!
you'll pick up really good info from the links other people have done and hopefully by now will know that you can eat fresh meat (need to check sausages though, and some burgers, because they often have breadcrumbs in as a filler), dairy products are fine, fruit and veg. Bread's the big no no, and anything with wheat in - biscuits, cakes, anything breaded - fishfingers, breaded fish etc.
If your diagnosis is confirmed you'll be able to get gluten free food on prescription - pasta, bread, pizza bases, biscuits, crackers. I find this very helpful as gluten free food is very expensive in supermarkets!
You'll find that g-f food doesn't taste the same as ordinary stuff - I've found that very difficult to get used to, but I'm learning to accept that that's the case and I'll just have to get used to it!
The endoscopy you'll have should be completely pain-free and only takes a few minutes. I was terrified before mine - turned into a jibbering wreck at my outpatient's appointment beforehand and cried all over the consultant. But the sedative meant I don't remember a thing and wouldn't be at all worried if I ever had to have another one.
Good luck and give me a shout if you need any more info!