Fermentation can either be really energetic, or really lazy. You can't really ever be sure, one way or another, what it will be like. The yeast are live fungi, so they do what they want to do.
If you don't want to buy bottles, you can use any bottle that comes from any carbonated liquid. Dark brown ones are best, if available, but beware of root beer bottles because the flavor is rumored to linger. If you do bottle into clear or green bottles, keep it out of high frequency light (sunlight, fluorescent light, etc.).
{maybe it's high wavelength light, I always get those confused: avoid high ENERGY light, yeah, that's about right}
When it's time to drink, there will be sediment in the bottom. The longer you leave it in the fridge, the more compact the sediment will be. Don't drink the yeast sediment -- it's not harmful, it just doesn't taste that great, and it can cause some people "intestinal distress" if they aren't used to homebrew.
Your beer is probably not contaminated. You will know because it will taste absolutely god awful. If you taste your beer, and it's rancid or smells like the inside of a racoon's colon, then DON'T DUMP IT. Set it aside, wait a couple of weeks, and try it again. If it is still reminiscent of the business end of a diarrhetic sphincter, then, well, sorry. It went bad. If it's good, then you just tried it too early.
Remember: the timelines that come with the kit are a bit "optimistic" on time... so give it a little more time and patience than listed there.
If the first batch goes badly, come back on here and we'll help you make a better batch. If you want, go ahead and check my recipes (especially the simple wheat in my sig) and you can make really good beer using the Mr. Beer fermentor but without the expense of the Mr. Beer kits.
If this hobby is for you, then you will be fascinated by the process. If you are more of a drinker than a brewer, there is nothing wrong with that -- I would just encourage you not to give up after only one batch if you think this hobby is something you would find rewarding over time.