I just got back from the car wash turned my car off and it wont start back up 12.1Volts with key in "on" 10.3 when key is turned to start and no solnoid "clicking", I need my car by tommorow.

 

So you get nothing when you turn the key? No lights, no turning over? If so, check the ground to the battery and make sure it's tight.

 

No everything elts works it just diden't start, I wated about 45 min and I just got it started (5 min ago)

 

Remember that a fully charged lead-acid 12V battery should develop 12.6V minimum. Even when a load is applied from the ignition system, the voltage should be at or above 12.6V. Obviously, cranking is a heavy load and will drop the voltage.

It sounds like your battery was discharged for some reason, and recovered by itself after some time, as a good battery should. Just make sure it gets fully charged before it begins to erode material off the plates.