First off, welcome to Android Central.
Did you buy it online or at a local retailer? If locally, then it shouldn't be a problem to take it back and exchange it. If you bought it online, contact them and find out about a replacement. If you just bought it 5 days ago it from an official seller (ie amazon, samsung) and not a third party (ebay craigslist) then it should definitely be under warranty and easily replaced. I agree, no need to spend your own money on an extra charger.
If you need additional help or have more questions or details to share, please join the site so you can reply in this thread. See
this link for instructions on how to join Android Central.