Yeah she is only so young. She hasn't experienced nor played with her body enough to see what pleases her. Be patient with her and give her time for her to enjoy things... you guys shouldn't be having sex if she has no clue how to turn her own self on or can't even turn herself on masturbating... why don't u guys take a break for a while and talk to each other and eventually get to experimenting with each other again and give her space to explore her body further... she needs some down to her own time and to touch her body and stuff... she has to have that frist before she can tell you what she would like u to do. Give her time and patience cuz she might feel like she is rushing things and trying to please u so she is worrying and stressing on how to turn you on and lost track on how to turn herself on...

The first thing to be concerned with is the pain in the stomach. At that age her genitals are not fully developed. No matter how much they may seem to be, they are not. She should get this checked out.

At each of your ages, the stress of the risk of pregnancy is enough to stop orgasms. I started about that time and it was not worth it. I backed away from male-female sex until I learned more about my body. She is very likely having a stress reaction and the orgasm is a fragile bodily response that can easily be lost.

Get the pain checked out.