There are many diseases of the gastrointestinal tract that have overlapping symptoms. Your stomach problems could be due to many different conditions. Crohn's disease is a disease where the body's immune system attacks the gastrointestinal tract. The symptoms include diarrhea
which can be bloody, fatigue, weight loss. Crohn's is common enough that it should be suspected or considered when someone has a diarrhea with crampy abdominal pain
that won't go away. If you suspect you may have Crohn's disease, then you should seek treatment right away.
The wheat allergy you referred to is part of the condition gluten sensitivity enteritis, or celiac sprue. This is a condition where the immune system attacks the inner lining of the small intestine, but only when a certain wheat or rye protein called gluten is consumed. Removing gluten from the diet is the treatment. Some people need to remove gluten from the diet for more than a year to get relief from their symptoms. Keep in mind that if you go on a gluten free diet, it will make it harder to diagnose gluten sensitivity syndrome.
You should start by scheduling an appointment with your primary care physician
. He or she will be able to give you a thorough evaluation and either make a diagnosis, or refer you to a specialist.