Removing objects stuck in a disposal will need to be done even after you get it freed up. Disposals will not grind up certain things, so removing them is the best course.
Coins and rings are a couple of things that can jam a garbage disposal. They get wedged between the turntable and the side of the housing and can be difficult to dislodge. Try to locate the object if you can.
I know, you were probably trying to use it when the jam occurred. Try to remove the water and food and see if you can identify the object. Use pliers, a screwdriver or tongs to get it free. No fingers, please.
Once the object is free, use the tongs to extract it. Go back to the allen wrench and make sure the jammed garbage disposal is moving freely now.
When it is moving freely, you can remove the wrench and turn the power back on. Check to see that the disposal is working correctly. It's grinding and the water is going down? Wonderful this jammed garbage disposal will soon be a forgotten memory.
Prying the Disposal
Prying a jammed disposal with a broom handle or another similar object is not a good idea. See the article 'Using a Garbage Disposal Wrench' for the best method on freeing up a jam.
I'm not sure whether using a broom handle to free a jammed garbage disposal is a last resort or creative thinking. If you don't have an allen wrench and it is too late to go out, it is creative thinking. If all else has failed then it is a last resort. I do not believe that a broom handle will generate much more force than the allen wrench and a pair of pliers would. If it makes you feel better, try it.
At this point, you may be faced with a tough decision. Assuming you cant' free up the motor and you cannot find an object that can be removed, you may be faced with replacing your disposal.
Try one more time with the allen wrench to worry it loose. Still stuck? I feel your pain. A new disposal will run between $75 and $200. The difference is for power, features and whatever else they use to get you to spend more. It will take an hour or so to replace.