I need help y’all ... 16 year old girl in Distress

Hailey

Ok so my period are hella bad... like I’m talking my cycle is very in and out sometimes it will be 30 days and sometimes it will be 35 and then sometimes it won’t come at all. I get really bad cramps they feel like stabs in the side then they will go away after about 30 seconds to a minute of sharp pain. My periods are also about 8 days long . Should I get or think about birth control?