Sigh & yawn often

[Petruts]

Hello everyone. For some months i have  some weird symptoms like i have to take deep breathes after two normal ones and after that i start to yawn a lot and also very deep , sometimes i can not take it to the end. Last year in November i went to doc, blood tests ok, the x ray for lungs ok, EKG and cardiac ecography also ok, spirometry in parameters, the doc said is anxiety but i am not feeling ok..even when i am not anxious i can feel these symptoms. Could be the nose? I often have stuffy nose. But i should not  breathe better through my mouth?  i can not feel any improvement when i breathe through my nose or my mouth ..this ruins me and I am afraid to do a lot of activities.. anyone who can help with any advise or passed through the same situation. Thanks a lot