When I fell stressed about gambling whether not for making a good profit or for losing on match or for losing a good amount I try to watch a movie or dram and I feel better after watching movies as well as dramas. Also, I stay away from gambling for a good number of times so that it can't affect anything on my health. If I do not do this then I can't concentrate on any of my tasks whether offline or online.
Playing sports or games is also a good way to calm your nerves. I believe most of us like playing video games, and others would love at least some game of sport; whenever we feel down because of losing money in gambling, we can do what we usually like doing so that we can get our thoughts away from gambling and lose focus from what we've lost because if we keep thinking about it continuously, the urge to recover the money will keep getting stronger and eventually, we will gamble again only with the intent to recover our money and that can be disastrous.
You will rarely find a person who would tell you that they have managed to recover their money after losing, spending some time away from gambling, and then gambling in rage with the intent to win more than what has been lost. Most will tell you that they've always lost more money in such situations. Hence, the best thing to do is to stay away from gambling for a while. What's gone is gone.