Chest pain followed by being breathless.

I'm 21,Ive been a bit overweight.I've a history of asthma.Recently i've been having this sudden chest pain followed by being breathless..I thought it might be my asthma,so i just use my inhaler as usual..the pain lasted about 15min..After 2-3 days i had this attack again...but it lasted longer..wen to visit the doctor,she diagnose me with muscle pain and give me some pain killers..But my breathlessness is still there..Yesterday it happen again..same thing..pain and breathlessness..Went to see a doctor again.he said i have anxiety due to stress or over work..He gave me some sleeping pill to relax..I have 2 different diagnoses..But i still have this pain in my chest and breathlessness..I need some opinion in what should i do...?