We can say gambling is wrong if we lost money on gambling, and if we earn money from gambling, I think you guys would never say that, haha, so every statement about gambling is based on the results, sometimes we are down some money but sometimes we are up, just cash out when you are up, that must be correct. 
yeah we need to try gambling ourselves before make any statement if gambling is wrong or not. There are many people who stating gambling is great or wrong, but I'm sure most of them don't do gambling yet.it doesn't matter if you win once or twice, you should always check your results in the long term. for example check your total invested against total profit in a month or 30-40 days period to see how much you have lost and how much you have earned through your total gambling.
then you can easily decide whether or not gambling is wrong for you.