Notebook Boot and Lockup

The other day, for the first time, I knocked a glass over near my laptop. The splash landed on the bottom right of the keyboard so i quickly wiped it clean and left the laptop keyboard-facing-down for a while in the hope anything would drain out.

Unfortunately, despite my laptop operating absolutely fine in nearly every scenario, the laptop immediately failed to boot the next morning after being turned off all night. At first i thought it was broken for good, but i restarted it using the power button (which glows when pressed, so i know its working) and it booted fine. If i shut it down again, it will boot fine the next time. However if its left off for a long period of time (e.g during the night) it wont boot the next morning without following the same steps. Turn it on (no sounds, no fans, just a solid LED on the power button), hold it down until it goes off, press it again, and then the fans go and the computer starts.

After reading online i believe this is a damaged capacitor. My laptop is under warranty for a further 3 months but i dont think this kind of damage is covered. What can i do if the capacitor is damaged? and if it isnt? what's wrong? Thanks!