Period was due today, didn't show up, emotional state is out of wack(cry on cue anyone?), and having…

Period was due today, didn't show up, emotional state is out of wack(cry on cue anyone?), and having some sharp stabbing cramps on my left side(ovary area). bfn 10dpo-13dpo. not to mention my hair is shedding like crazy (happened with my other pregnancies). guessing I'm just going to wait it out. ugh why do our bodies do this?