Well congratulations. It looks like you HAVE started your period. That brown stuff is just a tiny bit of blood that didn't make it's way out immediately. Don't worry, more will come later. It's not unusual for a period to start this way. Nothing to worry about.
It's normal for women to start their periods as late as 16 years old. It's also normal to have abnormal cycles when u start having your period, so I'm not surprised it's really light and brown, not red.
If you have more questions, just talk to your mom/aunt/older sister - periods aren't so awkward to talk about as you think, especially for those of us who have been having them for years. It happens EVERY month - you'll be tired of it in no time. Good luck!