Help please, 99' interior light trouble

Hello. I'm new to the forums. I decided I'd come here with my problem before taking my 1999 cavalier to the dealer. When I open my driver's side door, the interior light doesn't come on, only once in a blue moon it does. But when i open the passenger side door, the light always comes on. When I take the key out of the ignition, it always comes on. The only reasoned I'm concerned about it is because I just got my alarm installed last week. My dad thinks its something with the fuse. Please, anyone help me. This is my first car and I love her!!!!

When you open your door, see if the little black button is pushed all the way in or stuck. This is what turns the lights on/off when opening the door.

When you open your door, see if the little black button is pushed all the way in or stuck. This is what turns the lights on/off when opening the door.

If I slide the button all the way up, the light will just stay on, all the time, I have it all the way at the top before it clicks into position.