Has this happened to anyone with Oatmeal hot cereal

Every morning I would have oatmeal for breakfast. But I could not understand why all of a sudden I would have shortness of breath. So a couple of days ago I didn't have time to make oatmeal for breakfast and I had cold cereral and my breathing was much better. So I put two and two together and figured out it is the oatmeal. My breathing is not perfect but this is because I have to wait for the oatmeal to leave my body totally and I will take an antihistamine tonight.

You could be having a reaction to the wheat in the oatmeal, was the cold cereal you ate rice or corn based? Food allergies and intolerances can develop slowly over a long period. The body can manage them for a very long time and you won't feel any adverse affects but over time the body loses that ability and you can start to feel the effects.