A hard kick feels just like a tap from the inside and is easily recognizable.
The rolling over feels like a something brushing up against you from the inside, but with more pressure. It really does feel exactly like you'd think.
Early on it is easy to miss or ascribe to something else, but the feelings I have been getting recently are so much more definite.
I'm only a few weeks ahead of you but for me, baby rolling just feels like pressure. Kicks/punches feel like just that, like something inside you jabbing at you (it actually kind of tickles)...they started not so strong but now I get some that make me jump. I can definitely tell the difference between movement in my uterus and gas/indigestion.
ETA: try pressing on a place in your uterus and see if baby kicks you there. Last night my cat was laying on my stomach, stood up, and put some pressure on the side of my uterus. Maybe 30 seconds after that I started feeling very distinct movement/kicks where the cat was pressing, apparently baby didn't like the cat intruding in her space.
I'm not sure what rolling over feels like, although I've had some pretty weird feelings lately.
At first, movement felt like little gas bubbles or flutters. Then it felt like gentle taps and flutters. Now I get very distinct flutters plus definite poke-poke-pokes from the inside as LO kicks me. I can see the kicks from the outside as my stomach moves and they start at one side of my stomach and eventually move to the other sometimes.
Usually he just wiggles around gently in there but lately when he's awake he's been kicking me pretty well. Sometimes I think he gets my bladder because I have a sudden urge to pee.
Occasionally I feel a lot of pressure and almost feel sick and I wonder if that's him completely rolling over or repositioning himself in a big way.
kicks seem harder than punches which are more like soft taps but kicks move my belly, at least thats my guess. the rolling over i think feels like the empty feeling from a roller coaster, but not in my stomach, in my uterus