Yeah, I forgot to say it, but there was a moment of initial resistance for me too, at that point it felt just like in real life, and then I pushed a bit harder and suddenly it went in real easy. Shortly after that I pressed both hands up against my window, which felt normal at first, and as I pressed slowly it suddenly felt like tight-stretched cellophane (cling wrap) and bowed outward pretty easily. I pushed a bit harder yet and my hands just popped through and my head popped through right behind them. And the moment my head went through the sound changed - from the quiet of my room I was suddenly hearing a gentle susurrus of crickets and a few birds singing and a light breeze.

I know the last bit is slightly off-topic, but I thought it was relevant because it shared the same initial resistance and then popping-through.