If you washed your mobo by watching a youtube tutorial, you took an extreme risk. Now since you are running your computer, I assume you pulled it off and in all likelihood your keyboard is the one which is at fault. Try replacing the keyboard since it is the cheapest and easiest way to find out rather than replacing your mobo. You can also try a different keyboard from another (preferably similar) laptop to check, if you are confident enough to disassemble and reassemble them.