Acute Pain to Left Side of Chest, Can’t Breathe. What is it?

For no reason I get acute pain to the left side of my chest every so often (maybe 3-5 times a month). During this extreme pain I am unable to move and collapse on the floor. Curling up into a ball helps alleviate the pain. I am also unable to breathe, eventually after about 30 seconds I am able to take short breaths and after about 1-2 minutes am able to stand back up. I’ve used sites like WebMD.com that say it could be pulmonary embolism while others say it could be a panic attack or acid reflux. A doctor once told me that it’s probably just muscle spasms, but he didn’t run any tests. I am a 24 year old male and this has been going on for about 6 years.

My friend and I both had those same pains and he checked out with pnemonia and my pains just stopped…. I couldent even stand when these “attacks” came on