Should I go see a doctor?

Hello my name is Hannah and I'm 16 years old will be 17 in December however I have never had regular periods I started tracking them at the beginning of this year here it is:
Feb 29-March 3
April 7-11
May 12-17
July 6 light brown spotting not enough for a pad
August 22-
These are all the periods I've had since January...Is this normal? Should I be worried? Should I get it checked out?