Is there a non-invasive way to determine if you have crohn's disease?

Crohn's is an inflammatory bowel disorder causing GI tract lesions and other specific symptoms outside the GI tract. Common symptoms include diarrhea, abdominal pain, rectal bleeding, fever, weight loss, and fatigue. Fecal calprotectin test can help rule it out, but a blood & stool tests and imaging can determine other causes. Endoscopy and imaging are essential for diagnosis & monitoring

if what you are saying is you think you may have a debilitating condition, but you are restricting your Physician's diagnostic ability by restricting testing techniques, you are not being fair to yourself. You are also not being fair to your Physician. See a specialist Gastroenterologist. Discuss available testing and the knowledge that may be missed if you tie his/her hands.

Blood tests help in narrowing the possibilities, however, definitive diagnosis would require endoscopy, biopsy, and radiologic examinations.