Hi, Was Playing With My Dog In The Yard Throwing

Hi, was playing with my dog in the yard throwing the ball and there was a lot of dirt and grass on it and a few hours later my hand was extremely itchy so I had to scratch it a few times then the next day it was so sore and it had a couple of blister type marks now it's like one blister but a couple mm long and the doctor put me on Famvir