any idea's what my problem is

I AM BEGINNING TO WORRY .SINCE MONDAY WHEN I WOKE UP.IHAVE BEEN HAVING THE REACURRING PROBLEM.WHEN I LAY DOWN AND GO TO SLEEP
WHETHER ITS A NAP OR WHATEVER WITHIN ABOUT LETS SAY APPROX.2 HRS I AM WOKE UP BY PAIN DOWN BOTH SIDES OF MY RIBS ACCORSS MY BACK AND IT HURTS TO BREATH.AFTER I HAVE BEEN UP AND AROUND FOR ABOUT AN HOUR THE PAIN GOES AWAY.BUT THEN WHEN I LAY DOWN AGAIN THE SAME THING HAPPENS.I AM A 57 YR OLD FEMALE SMOKER.THANKS

[National Jewish]

Having chest pain as you have described can be from many different causes.  These may be related to muscles, ribs or your lungs.  If this problem is not getting better, it is a good idea to see your doctor and have an examination and possibly a chest x-ray.