Do you believe in luck? And if so, do you think it is a lucky event or a lucky time period?

If you have one lucky thing happen to you, do you try to ‘push’ your luck and see if it will continue, or do you see this as an isolated lucky-thing-then-maybe-unlucky-thing?

For example, today I found a skirt in a shop: last one in the store and exactly my size. If you had a bit of luck like this, would you try to do something else in which you might have good luck? Say, ask someone out or call into a radio station to win tickets or something?