Key is stuck
 

Was replacing my Nak stereo with a replacement one I bought off Ebay and now have my key stuck in the ignition. During stereo replacement, I had to turn the key on to get the shifter back so I could remove the center console and eventually swap out the stereo. Apparently, somethings gone wrong. Was wondering if this is a security device thats been engaged cause when I pull a battery cable off and while its off I could turn the key to off but once I put back the cable and eventually start the car again, the key gets stuck.

Thanks in advance for your responses.