Hi Need Advise, Im 28 Fit Healthy. Two Weeks Ago

Hi need advise, im 28 fit healthy. two weeks ago i woke up and couldnt breath and took bout five seconds before i couldnt take a breath in. Later that day ive felt like i wasnt absorbing enough oxygen when i was breathing. And having constant chest pains and the other day i got angry and it felt like i could feel my heart pumping blood like when u squeeze a sauce bottle and you feel that splutter sound.. Ive been to a doctor and they thru it off as bad diet.sleep n smoking but did no tests.. I feel there is something wrong but dont know wat to do.. Can i help ?