I also tried a bit on Luckyb.it but that wasn't too great. I think I broke even there.
So what now?

I would keep doing it, but be smart and put aside your profits. I mean you started with 38, so withdraw all that is above $38 and try to do it again. That you will not end with a loss and have a chance to keep winning some. If things start going wrong you always have the chance of just withdrawing the remains and stop for a while.
Good advice actually, you already win because you are lucky and when your strike luck it will give you a good amount of money so you need to be wise and withdraw your winning as if you will continue to gamble then for sure you will lose eventually. If I am lucky then I would try to hit the jackpot so that if I win I would quit gambling completely and focus on legitimate business.