Period Question...or Pregnancy Question. Im Not Sure.

I normally have a heavy period lasting 5-7 days. Last month, it came four days late, but it lasted as usual. This month, it came four days before my normal due date, and it only lasted a day and a half! Two days later I started having a little brown discharge that has lasted 2.5 days. Could this be a sign of pregnancy, or is it just a weird cycle??