About 2 days ago, at 100% my Mac battery would last for about 5 hours. Yesterday, at 100%, my battery said its estimated last time was 2 hours. I tried calibrating my battery and this morning it said the battery would last for 5 hours again at 100% but then when it dropped to 98%, it went down to 2 hours again. I've been using my computer a little more frequently than I usually do, but not to the point where I believe my battery would drain out that quickly. Should I bring my Mac into the Apple store or is there something that I can do to help my battery?