3 Hours Remaining, Yet Fully Charged

Hi,

I bought my Macbook in the summer, so it's fairly new. I've been very happy with my battery until the past few days. I noticed my Macbook heating up and the battery draining. I let it drain and left it dead for five hours then charged it. Here I am the next day, and it began at 99% and said there was 3 hours and some minutes of lfe in it. It's down to 89% under thirty minutes later, while I'm writing this, and now says it has 2:58.

I'm on 10.7.5, by the way. Again, fairly new.

Any info anyone can give me? Since it is under 5 months, it's got to be covered, no? Not fair. I spent 1200 bucks thinking this wouldn't give me issues mere months later....

😟

Thanks for reading.