I think you should be seen if you are having trouble breathing, but I have 2 further thoughts.

First, if you're truly having trouble breathing you need to be seen immediately.
Second, the trouble you're having is most likely anxiety or panic. The reason I'm saying that is because if you couldn't breath you wouldn't be posting online.

Here's an idea:
Lie down comfortably. Place one hand on your chest. Place the other hand on your stomach. Take a full, deep breath so that only the hand on your stomach moves. The hand on your chest should remain unmoving. Try doing this several times until you have a good pattern of slow, full breathing going on. Don't hyperventilate. Breathe normally, but from the bottom of your lungs. Make sure that only the stomach hand moves.