Talk to Chest Respiratory Specialist on Pain In Left Side Of Chest

I'm 19 years old amd facing this issue since last 6 months. left side py chest mn pain tha... achnk khichao hota tha r 15-20 seconds k bd khud hi khtm ho jata tha... r 2 month sbd takreebn khud khtm ho gya... but since last few days I'm facing this issue again and this time it's worst.... achank khichao hota h left side chest... r kbhi kbhi left arm r chest mn khichao r drd uthta h... it's like squeezing... shortness in breath... sans leny s b hota h jb essa ho... mjhy sans rokna prta h taky drd khtm ho... irregular hertbeats hn... jb mrzi teez ho jati h... heart py dbao rehta h r kbhi kbhi essy hi dbao s hlki hlki chubn rehti h dil k aspass.. I want to know what possibilities hn... Why it's happening...? it''s not on right side... it's on left side