I have seen someone that fainted before because he lost. It was later that people knew he fainted because he lost a bet.
People around would have thought that the guy was asleep and didn't want to bother him only to find that that he has passed out because he's been "asleep" for long time 
Anyone in a bet shop will see different emotions that people exhibit when they lose. Some cry, some just laugh hysterically while some others just begin to ruminate over their lives and the poor choices that they have made that have brought them up to point.
Since I use little amount of money to gamble, even if I win my bet, it wouldn't show on me because it's a little amount that my win will be. Gambling for fun is the safest way to be in control of your emotions and limit your losses.
When I lose the emotions doesn't linger for more than 5 minutes. The only thoughts that I have is what I could have done differently. After that brief review, I will forget about it and get busy with something else. I don't spend too long at it.