Film advance lever stuck

Is there film in the camera? If so it may be at the end of the roll and thus when advancing the film it jammed. Rewind the film then see if the lever and shutter operate. If not then a CLA is needed.

Without film in the camera it may well read before zero, my K1000, K1000Se, and K2 do that. Press the film rewind button, maybe that will release it for you.

For camera repairs look to:
Eric Hendrickson: http://www.pentaxs.com/index.html

A Canon AE-1 is not an EOS camera the Canon "A" series is manual focus while EOS is auto focus. First thought In answer to the advance lever stuck or jammed I'm going to assume the camera is in serviceable condition and has not been subjected to water damage or harsh use. If we are dealing with just the advance lever then I'd say that you have over advanced the film at the last frame. I've done this myself after loading a 24 exposure and thinking I had a 36 exposure film. At the bottom of the camera there is a little pin which releases the advance lever and allows the user to rewind the film. Under normal conditions when it's time to rewind the film into the canister this pin offers little resistance to pushing in to release, however depending on how much force the advance lever has been subjected to increases the tension on this pin. Push the pin in and rewind the film.
Second thought is if you have film in the camera and it has not been used fully then it's possible that the film has already been advanced to a new frame and the shutter needs to be activated before the lever will become free and advance to the next frame.
Other problems with the Canon "A" series cameras is they have a tendency to dry out the lubrication and begin to squeak when the shutter is fired. This condition can eventually result is a shutter seizure and give the same advance lever condition.
Those are the three things that come to mind over this lever problem lets hope it's just run out of film.

Hi fmerlin, If you have film in it you may need to remove the film to free up the advance lever. Go into a closet cover under a blanket etc. Also, Walmart and most drug stores have a big change bag that they could do it for you. With film out it still will not advance it will need to go to Nikon.

Rewind film and take it out the camera. Try advancing the wind lever.
If the wind lever does not move, you have jammed advance mechanism.

push the film release on the bottom of the camera and try to continue forward then. If you are trying to get 27 pictures on a 24 exp. roll you may have advanced your film so far that it is stuck on the piece of tape that attaches the film to the spool. Take only 24 pictures.

The film is either at the end or stuck. The shutter will not release unless the film advance lever has gone all the way and back.
Make a note of the frame counter. Rewind the film and remove it from the camera (When you feel the film to come loose from the receiving spool, stop rewinding to prevent the end of the film to disappear inside the can. This way you can reload it if it was stuck in the middle.) If the film was completely exposed, take it to be developed.
With the empty camera, try to advance the lever and release the shutter. If this works, the problem was the film and not the camera. Everything is fine. If the problem persists, take it to be repaired.
If the film was stuck in the middle, load it again into the camera. With the lense cap on (preferably in a dark room or similar) 'shoot' as many 'empty' frames as you had on the counter plus two more. Finish the film and develop the pictures.
If the film stucks again at the same place, rewind it and develop normally. It was a bad film.
Hope this helped you to solve the problem.

needs repairing at a qualified shop
when was it last cleaned or serviced ?
if you think the camera is worthy, since its old how much is it worth to you vs a new one

if the lever feels soft then you might haven't moved it till the end so try to push it untill u hear a tick if not then it's the capacitor