At the end of 2018, Apple announced that “limited number of 128GB and 256GB solid-state drives (SSD) used in 13-inch MacBook Pro (non Touch Bar) units have an issue that may result in data loss and failure of the drive”.
So you are trying to use your MacBook, on battery, and it seems that the battery life gets shorter and shorter before you have to plug it back in. Well you aren’t going crazy, every time your battery drains
Update: macOS Sierra is now available. See more detail on the post macOS Sierra Now Available As of tomorrow 9/20, Mac owners will have the option to upgrade to the new macOS Sierra operating system. Up to now, the Mac operating system was known as