I am 18, 5 7 and around 120+lbs (haven t weighed myself in a while) with no medical history of any diseases or alergies even. For a while now (i think around a year or more) I have had trouble breathing. In the beginning it was merely shortness of breath for a few minutes and then it would pass, but it is happening all the time now to the point where it barely ever stops. It basically feels like i cannot get enough air into my lungs or breath deeply and my heart race increases to the point where i can feel it through my stomach and throat as well as my chest. Also, a while ago I was outside and got these symptoms at which point my eyes went black and i could literally see nothing (despite it being the middle of summer and daylight outside) and i could not tell which way was up so when trying to find a chair through the sightlessness I hit my head on a treebranch and fell (my mom caught me before i hit the ground) at which point i heard a loud ringing in my ears and could no longer hear anything. After a few minutes i regained my sight and hearing and after going to the doctors she said it sounded like i couldnt get oxygen to my brain and so i passed out (kinda). She sent me for various tests (heart and lungs) but everything came back normal. I have no idea what is wrong but it seems to be worsening and its not stress becuase i m under no stress and i didn t get it during exams or anything stressful like that. What is wrong with me?