Key will not turn after leaving the headlights on for 45 draining the battery?

Sometimes the ignition key will get stuck when there is no power to the car. I would lift the hood and remove the battery to take it to the auto parts store for testing, replace it if needed which should fix the stuck ignition key. You might want to try moving the steering wheel back and forth while turning the key this can sometimes work. Please go over this guide as well:

https://www.2carpros.com/articles/ignition-switch-wont-turn-stuck

Please let us know what happens.

So it sounds like the ignition tumbler is worn out and needs replacement, you can try spraying WD40 inside the tumbler to see if that helps but if not here is how to replace the unit, I would try to get it from the dealer. Check out the images (below). Please upload an image or short videos in your response of the problem, so we can see what's going on.