I dont know what is going on?

I have no hypothesis what is going on with my body. I own had my term for three years and sometimes it was close to 3 to 4 days late. I be supposed to start my period tuesday and today is Saturday, i haven't have sex or anything. So it coudln't be that i'm pregnate. I dont know what is going on. maybe i counted my days wrong. SOMEBODY HELP ME.
Answers:

Any suggestions on why for the concluding 2months?

Your cycles will change through the years. everyone is different, but I even skipped mine occasionaly.

Also...if you are around other women your body will sync near theirs and you will cycle together. This happens to alot of population.

Is it common for an 18 year behind the times to have their mane fall out strand by strand? Why is it doing this?

Sometimes stress delay periods. I would hand over it some more time and if it still doesn't come then phone a doctor, but I wouldn't worry immediately because that's probably what is causing it surrounded by the first place!!

Why do girls have orgasms?

well that happen to a girl at my school but it be because her brother masturbated in the bathroom and some get on the toilet seat and consequently she sat surrounded by it and got pregnant