Fixing my American Standard Faucet
I am trying to fix a shower faucet stem I have replaced the rubber washer at the end it is double faucet american standard faucet with a hot stem at the end of each end when I put it together I can't get it to turn off or to stop turning its like the whole inner stem keeps on turning in the off direction I'm afraid to turn the water on thinking it will get the inside of my walls wet

Would this be your shower valve? (see image)