You guess at which liquid you need, assuming blue would be lighter in tone and prop yourself up carefully, just barely able to reach the shelf. As you are about to grab the final component, the rotten wood of the shelf gives way under your leaning weight causing you to fall back to ground yelping as the three vials hit the ground. They break open, splashing you and creating a volatile mixture which immediately explodes..
..you try to scream but can only muster a loud cry as the world goes black..