Stop light surging, lurching??

I just got my 2014 and still getting used to my first hybrid but today I felt something strange. I was stopped at a red light in EV mode with the engine shut off and while holding the brakes, I could feel just a slight lurching like something behind me trying to push the car while I hold the brakes. It's hard to explain, its like the feeling when you let off the brake and the car moves forward but it was trying to do it when I was holding the brakes. it was very faint and I barely noticed it for a few seconds until the light turned green. I was never able to reproduce it and I'm questioning my sanity if it was just heavy wind pushing on the car..