Do dogs get allergies? If so, can I get something at Petsmart to help?

[Barbara G]

We were removing some pinestraw from under the deck that has been there for a while, and she was playing around it most of the day. Now she acts all tired and is not very playful ( not her usual self, she is a 7 mo old boxer). I thought it might be allergies, but wanted to make sure dogs got them first. Since my vet is already closed, I wanted to see if I could get something over the counter for the night. Any info is a big help