Good luck with the tests.
I'm being tested due to my symptoms and family history. I get random bouts of diarrhea after I eat and will have intestinal cramping for days after the diarrhea. I've lost a lot of weight and can barely eat anymore because of how sick I feel after eating. I was dismissed with ibs but am now going to be tested for celiacs just to be sure.
Symptoms of celiac issues (or general gluten sensitivity) can vary between individuals. Some people have diarrhea, while others can actually present with consitpation. Still others have no blatant GI problems. Some have rashes, others don't, etc.
Yes, your symptoms could be due to gluten intolerance.
You're going to have to stay on gluten before having the test done. But if they're going to use the blood test, there's no reason you should have to wait until January to have it done. Almost any doc can order that test and it can be done quickly and easily. Make sure the full panel is done: IgA and IgG gliadin; total IgA and transglutaminase. Don't settle for just transglutaminase.
Anything can be normal and there are a lot of people who are completely asymptomatic. Are you being tested because you have symptoms or because of the family link?