F-250 Harley Davidson Security Issue
 

I purchased a 2009 F-250 Harley Davidson with 7k miles on it and have had it for approximately 1 week. Tonight I was just looking through the vehicle and using the remote transmitter... to my suprise some sequence of buttons I hit started the vehicle. I depressed the brake to shut the vehicle off. The remote transmitter has the typical ford buttoms (Unlock, Lock, and panic). I tried to repeat the sequence and couldnt. I used the entry keypad on the door and all of the sudden the vehicle started again. I again was not able to repeat this sequence. Now, I am able to lock the vehicle either using the key pad, remote transmitter, or lock button and the vehicle locks. When I try to unlock the vehicle using any method listed above it triggers the alarm function. Any idea what is going on?? to my knowledge there is no after market security system installed on this vehicle as I was only given the factory transmitters and they have worked up until this point. Please help.