Shortness of breath while exercising????

So I don't work out everyday , but I do often. Most days I feel perfectly fine while working out , but there's been two times where I feel like my breathing is  out of wack. It goes away after I sit and relax , wondering why I would feel like this only sometimes???? 

Hi:  Hmmmmmm can you be a bit more specific?  What do you mean out of wack?  Does your heart pound when this happens and do you sweat more during the wack?  Does it matter what exercise you do when the wack hits?

Concerned.

It feels like my breaths are short , kinda like hyperventilating in a way. I have to focus on my breathing and I panic and it gets worse 

I use to hyperventilate when I had panic attacks.  So much so that at first I tried breathing into a paper bag and that helped but they got worse and now I have to take medication.

If exercise brings on the shortness of breath, anxiety over it seems justified; altho,  this could be more than just anxiety/panic related.

I'd check with my doc and request an EKG or an heart monitor to rule out any underlying heart or blood pressure condition.

Do you take any medication?  Do you smoke?  Are you over weight?  So many reasons why your breathing can be irregular.  You need to see a physician.