Quite a few things you could spruce up.
if you want to create an eeree atmosphere, the first thing you could try is to not have such vivd colours within your film. Remember that colours don't have to correspond to how they look in real life. Manipulate your colours teh way you would with your composition. For instance, If a character is wearing jeans, they don't have to be blue. A viewer will accept almost anything so long as it's believable in the context of your movie. In the case of your flash, try not to use just a black screen to represent darkness, give us outlines of objects within the room, making us know it's dark, but want to see farther into the room. There are so many scary implications when you can immerse yourself like that. There were compositional choices you could make too to get a better effect. You could have had the can REALLY big perspectively in the foreground so that it takes up almost half the screen. Then, when the character opens the door in the background, the light from the hall lights up the words "red paint" on the bucket. And the guy just keeps screaming when he sees it.
Anyway, nice effort on it. Maybe research some composition basics and try substituting colours in ways you wouldn't think before.
