#1 Great expectations. It’s not impossible for a one night stand to lead to something more, but it can only happen if both people want it. You should approach a one night stand as a one-time thing only. If you feel like there’s chemistry, there’s nothing wrong with asking for a second date, but you can’t be angry if you are turned down.
Think about it like a casino: you’re playing with the house’s chips. You’ve already won – picked up a one night stand, so getting shot down – losing – just gets you back to where you started.