I usually get cramps 4-5 days before my period.but not this time.my period is due on the 22nd-23rd of july.any suggestions why? i've been excising.

No big deal. : Although you may be having periods for sometimes but you are still very young and the body is in the periods of adjusting hormones and building structures. Wait till you see your periods and then watch for symptoms in the next period. If you are sexually active and don't use protection then wait for the required time of period and if you don't see any then consult your GYN.