So I'm still a newbie, but loving having a beardie. I adopted an adult and she came with a full set up. It wasn't until a few days later I learned about changing the light every 6 months so I didn't ask when it was changed last. Will I be able to tell when to change it? Will it burn out or be dimmer? I was planning to change it at the end of May just in case it hadn't been changed recently.