I think it is just natural that we have this feeling or urge to regain what we've lost. Many gamblers surely experience it but in my case, I wouldn't go back right away. I would learn and study things on how I could win the next time I play and see what I did wrong or what caused me the loss. I think it would be unhealthy for your investmeny if you are going to be too regretful from losing so instead of letting the urge to regain, the best thing you can do instead is to strategize so that you can surely get back all that you've lost.