Rolling over???

Okay so I need the wisdom of some experienced mothers/nannies... Today Christopher was on his tummy time mat. It looks like a cloth surfboard with lots of fun things to look at. There is also a little pillow that he can rest his arms on and push up. He was holding his head pretty high and looking at me and smiling. Then he started to lean a little to the right...a little more... and then, he rolled over with a look of absolute surprise. Of course, I made a big deal out of it, clapping my hands and saying "Yay" in my best mommy voice. So then I put him back up and he did it again--same thing. Now here's my question. Does this count as rolling over? He did have the advantage of the pillow which gave him some height so I'm thinking this is just a prelude to the real thing. I guess I'll have to take the pillow off and see if he can do it just on the floor. Regardless, it was exciting and fun for me to see!!! We had a lovely morning on the trail where we went for a 3 mile run with 3 walk breaks. I don't know if you're supposed to run with the regular stroller, but it's not like I'm running fast enough for the stroller to go out of control. It was totally fun and totally brutal! But I love every second of the pain in my legs. There's a running blog I'm reading written by a new mom and she describes her initial attempts at running as the "Ultra Shuffle" after the gait that ultramarathoners have after about 50 miles. That's about what I look like after 1 mile! I'll take it!