I'm 13 And I Just Got My First Period 5

I'm 13 and I just got my first period 5 months ago, My blood is dark red to brown and I have small clots in my blood. All my friends have red blood and it comes out in the toilet, however nothing comes out in the toilet except small clots. I don't get many cramps but I still get some. My periods are still irregular by j have got one every month sometime. Is this normal? Thanks