Gluten intolerance?

Hello everyone, since my baby (8 months) has started eating grain cereal such as wheat, oat, spelt etc., she's had bad smelling diarrhea about 3 times a day. I‘ve switched to gluten free grain cereal (millet, rice) after a week or two and the diarrhea has stopped immediately. Is it possible that she might have a gluten intolerance and is there any chance a doctor could test for it? Apart from the diarrhea she was perfectly fine, but it still concerned me 'cause she's never had any digestive problems before. 👶