None of us can tell you that. What we can tell you is that you just quit a highly addictive drug, nicotine, and doing that will always make you feel anxious. That is the most likely source of your tight chest -- it's asking for more nicotine. Say no.
Seems like it is anxiety i just started experiencing it a few months ago..I have gone to the ER twice from it..I have gotten 2 EKG and blood test which everything came back fine..But anxiety works in funny ways..But when you can't get a good deep breath that is apart of anxiety i had the same problems..The tight chest can be from anxiety..If you go under anxiety centre it will show you all the results you can get from anxiety..I always go there to see if my symptoms are normal lol.Anxiety does weird things to your body...