Is it normal that i think i look good leaving my house, but when i look in ...

It could just be the fluorescent lighting, it makes me look like a zombie. You probably don't look as bad as you think.

I do that tooo!!!! I hate it! Like my freaking cat sheds like crazy, and I don't notice it until I'm out in the sun and I'm like "Yukk, where the hell did that come from?" That's a little different, but I know what you mean

Well sometimes it's the opposite for me.

As everyone else said, lighting. Lighting can look the difference between looking undead and looking good :). I notice natural lighting while looking in a mirror always makes you look better.

Arg I always have that problem in bar restroom mirrors. It's all to do with lighting:)