Period is weird

So usually my periods are 7 days pretty heavy, then in october i missed a whole period, in early november i had my normal period. But my scheduale was wacky during that time but, then in late december my period was only 5 days and lighter than usual. The first day it was SO heavy and the rest was light. Now i got my period again. Yesterday morning period was heavy with bad cramps like rlly bad framps and now its light with only brown blood as it looks like. Im 14 years old so what could this be?