Hello and welcome to Medhelp forums. Blood in bowel movements is always frightening. When you have Crohn's Disease, blood stool is a reason to see your doctor. It's also a change in your symptoms. Therefore, we really advise you to see your doctor as soon as possible to discuss this. It has been a few days, so have you see your doctor as of yet? Here is some general information about Chron's Disease https://www.mayoclinic.org/diseases-conditions/crohns-disease/symptoms-causes/syc-20353304. Blood in stool with Chron's can happen because the place of immflamation in the GI tract can change.
Another possibility is that the blood in your stool is another GI issue going on concurrently with the Chrone's. https://www.webmd.com/digestive-disorders/blood-in-stool#1 Evaluation is really the best thing to do at this point.
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