It can be part of the hug, and I've had it too. I went for a COPD test, and my breathing was fine according to that measure. It didn't feel that way to me though.

I took up deep breathing exercises I learned with a Yoga book. It helped me feel as though I had some control over the amount of air I was getting, which helped with the anxiousness that I felt when I couldn't get a decent breath.

I agree it is a VERY good plan to get your lungs checked, but it is likely an MS thing.

Cherie