was in attic for an hour without mask. could this cause issue?
Fiberglass can be bad for the lungs: http://www.lung.org/healthy-air/home/resources/fiberglass.html

However, for it to be a real issue, one needs a lot of exposure...typically someone that works with it daily as part of their job. 

The amount of contact a typical homeowner would be exposed to in their lifetime is not likely something to lose too much sleep over. 

For future reference, however, a cheap 3M dust mask is a good idea the next time you're up in the attic. 

Odds are you are coughing due to dust in the attic more than the fiberglass.