This pain is probably related to your sleeping position. I recommend that you use 1 or 2 pillows to modify your sleep position. I would begin by moving to the prone (
faceFace pain-down) position if you currently sleep in the supine position and vice versa. The next thing to try is sleeping left side to right or vice versa. Then sleeping propped up by 1, 2 or 3 pillows.
This is not something one sees with asthma and so is likely unrelated.
If you have never had a chest x-ray, that should be done.