Why does stress causes difficulty breathing?

I get DOB, cold hands, and feel like I can't pull my chest in enough to get a full breath, so my lungs hurt (ache) as if I'm breathing 30% usual.

This happens after I cried, and sometimes when I'm driving and it feels like its hard to turn the car around (which I do) and feel really light headed!!! I never hyperventilate, quite the opposite - I breathe slowly as if I'm too exhausted to be able to lift my chest up. There's no blind panic, just really chest pain like someone's sitting on my chest. I feel I cant breathe.

Sometimes I start to grab a perfume or cologne or anything that smells good to make me feel better. (oh I feel better when i smell something good! like my bf's breath! lol! love it!) And when my bf saw me spraying a lot of perfume on my pulse he felt sad becuse he thought I'm wasting the expensive perfume he bought for me!