I bought a battery and put it in car ran fine died a few days later took battery to be tested and the guy at autozone said it was defective and gave me a new one. Also had my alternator checked and it tested positive. Put the battery in the car and it ran good for about 7-10 days went to go start the car and it wouldn't start this morning.

Well my questions are

What are my chances of geting 2 defective batterys?

Are there any common problems that drain the battery?

My last question is my key is now stuck in my ignition and i can't get it out with the battery being dead and i can't get the car to shift out of park with my battery being dead. Is this normal or is there a problem with my ignition