Car won't shift out of park

I was driving when the rpms shot up and the car didn't want to go. I pulled over shut it off and when I turned it back on the check engine light was on and I couldn't shift out of park. I tried several more times to no avail. Then I got it to shift but when I pressed on the brake it started knocking a the shifter. The noise goes away when I release the brake. I had it towed home and now it shifts more often then not but the light is still one and the noise is still there.