Period help

My period is really out of wack. I'll have it one month, skip another. I don't have sex often so I'm not scared of pregnancy. Just wondering if this is normal for some girls?

I'm not on birth control and I don't take any meds. I work 8 hours a day running around and on my feet, but I'm not too stressed. I get 8 hours of sleep. Is it just my body?