You may have asthma or it could be allergic reaction
. But if you have chest pain
along with respiratory difficulty off and on,you should be checked up by doctor and must do investigations,like chest X-ray,ECG, echocardiography
,thyroid profile, Hb%, DC,TC. You shold avoid dust,smoke and foods which is causing this problems.Steroid+sulbulamol inhaler may help you. Thanks.