Was this a baby rattlesnake?

In June I was in Wyoming in a area known to be the perfect habitat for a rattlesnake to live. I was walking across a feild when I nearly stepped on a small snake. It was about 12-14 inches long and fairly skinny. It had a very distinct diamond print on it's back. The last 1-2 centimeters of it's tail were darker and looked like what I asume to a rattlesnake rattler to look like. It didn't ever rattle, but I was still pretty sure it was a rattlesnake. I don't remember it's head being diamond shaped though, and I didn't look close enough to see and other features. Do you think it was a rattlesnake?