Hi RK and again, welcome! (I responded to you in the first post that you tagged onto as well)
Chest pain can be caused by tired and over worked thoratic muscles.
When we are anxious, we tend to over breathe in a shallow manner. This hyperventilation is usually not even noticed by us until we experience symptoms from it.
Chest pain can be result...and as Soul suggested above...breathing exercises can really help.
Here is my personal favorite. Give it a try and see how you feel.:)
The Divided Breath:
Imagine your lungs as having 3 parts. The bottom third, the middle, and top third. On the inhale fill the bottom third first, then the middle and finally the third. Make sure that this is one continuous breath, but divided, with a slight pause in between each third. Hold the breath in for 3-5 seconds if possible. Exhale in reverse. First blow out the top third, then the middle, and finally the bottom third of your lungs until all air is expelled. (remember the pauses) Repeat several rounds for a toatal of about 10 minutes. Practicing this every day will not only give you control and structure to your breathing, it will strengthen and loosen the thoractic muscles, allowing better, more productive breathing, and relieving the chest tightnessS.C.