Whats an essay?

Wikipedia.com says an essay is this...

"An essay is a short work that treats a topic from an author's personal point of view, often taking into account subjective experiences and personal reflections upon them. Essays are usually brief works in prose, but works in verse are sometimes dubbed essays (e.g. Alexander Pope's An Essay on Criticism (1711) and An Essay on Man (1733-1734). Many voluminous and famous works refer to themselves as essays (e.g. John Locke's An Essay Concerning Human Understanding (1690), Thomas Malthus's An Essay on the Principle of Population (1798)).
Virtually anything may be the subject of an essay. Topics may include actual happenings, issues of human life, morality, ethics, religion and many others. An essay is, by definition, a work of non-fiction, and is often expository."

today i had to write an essay. i had to take a test for the international school, and the main part of this test was that i had to write an essay. now for my i love writng, i mean what am i doing right now? writing. i like to write. and i've won a writing contest in the past, not only do i enjoy writing but i've been told i'm good at it. but today i had only two things i was allowed to write about, some dumb poem and some dumb excerpt from some dumb book. all in all very dumb, dry, boring stuff. but had to write an essay about one or the other. at least i had some choice. so i decided i could squeeze more out of the story excerpt than from some short peom so wrote about that. it sucked. i wrote 519 words about it and i was done. that thing was crap. my essay made no sense. it was all over the place. and i'm sure it would have just bored any one who read it. but i did it, and thats what matters. my big problem was this: what's an essay? i mean i know what an essay is but how am i supposed to write an essay about a poem or a story excerpt? i could have written a great piece being critical of the poem or the story, but an essay? what did they want me to do? analyze it? write my opinion and thoughts of it? i dunno. i kind of mixed all that. it wasn't great but whatever. as long as its done. but now im tired, i've written enough today. i'm gonna go now, bye bye!!