Laptop battery issues

Hey, my Acer laptop that I always keep plugged in seems to sometimes (weeks may pass between) drop 5% of charge. One time I found the battery light blinking in an orange light which did promptly stop after I unplugged the charger and plugged it back in. It has been over a month since then and this incident has not repeated.

When the charge drops while plugged in, it does charge back to 100%, but I'm wondering if these are signs of bigger trouble or just something the laptop does due to being plugged in all the time?

I've checked the battery condition with the Ace Care Center that comes built-in and it tells me everything is fine, but I'm not sure if I can trust it that much.

The laptop is almost a year old and I've not had other issues with it.