Make a video, post the link, and watch the awesome critique flow in

Lol, you say that like it's money or something. Good point of view.
Anyways, being skinny has nothing to do with roll pain. I am 6 feet tall and now weigh 140 lbs on average. I've lost some weight over the past few months. Now if I'm not skinny, I don't know what is.
I don't feel roll pain regardless of what surface I roll on, concrete, grass, gravel. Check your form, remember not to 'flop' from your feet to your back, the roll should be smooth, also, try to keep the angle of transgression over your spine as smooth as possible. And when you come out of the roll lead with the same foot that you went in with. AKA if you rolled onto your right shoulder, lead out with your right foot.
But A video would be nice.