My load is a 20ohms resistance under water, I don't think it may short.
Well, your inductor guess may be right! I'm using just 12 turns on each side of a green core (probably iron powder), and noticed that one side has 12 turns and the other 14. Also, only the positive diodes are burning... Does it make any sence?
I'll have to rebuild the PCB cuz mine is ****ed up already, then I'll try again with a stronger inductor.
Man, thank you so much for your help!