At your age, whacky periods are totally normal! :)
I'm 15 right now and I've had my period since I was 12
How old are you? My periods were whackadoo for a couple years when I was young. My doctor put me on a very low estrogen birth control pill and then my periods came and went like clockwork. If you are not interested in going on the pill, that is ok. Long periods are normal.