iPhone 4s battery issue

Hey there,

Just a quick question about my iPhone 4s. Over the last few weeks I've noticed the battery life has become horrible. I paid attention to it this morning on my trip down to work. And within an hour it dropped 13%, with just listening to music, and checking twitter for 10 minutes. I had no apps running in the background, siri disable, and location services turned off.

Also, I've noticed a new buzzing occasionally when I talk on the phone. And if I tap the phone, it sounds as though something might be loose inside.

Question is, if I take this into an Apple store, will I be able to get a replacement phone? Even though I purchased it in a Telus store (Canada) this past fall, approximately two weeks after it being released.

Thanks for any help or direction!