I left my mirror open over night now that light is very dim.
how can I replace that

Are you sure you didnt adjust the dimming on it?

bulbs dont just dim.... they go out... its either not getting the correct voltage, or the dimmer adjustment is moved.....

if you need to replace the bulbs, just pop off the lense with a screw driver (from memory?)

you guys got me the dimmer was on low. duhhh

Well, it had to be either that or the battery.