I'm renting a condo from someone, and I had someone come stay out my place in the 2nd bedroom (3 months after moving in) and when they went to use the guest shower, they had no hot water. Cold water comes out fine, and at full force, but as soon as I get to 12 o'clock on the knob, the pressure drops off until its almost barely dripping out the further you turn towards hot. And then, the water doesn't even get hot (maybe luke warm at best).

I'm terrible at describing things that I know nothing about, so here's two pictures.

In the 2nd pic you can see that the water is barely coming out.

The faucet is MOEN. I don't even know how to take the darn thing off. I started to unscrew the 2 screws in there, but they are so long that they eventually hit the knob and can't be moved. I'm afraid that if I pull the knob too hard, it's going to break.

Can anyone help me out? Am I at least looking in the right place? Is there a trick to getting the knob off without breaking it?

Thanks so much to anyone who can provide some helpful information.