Hello every one,

 

Ok so Just turned 21 years old i have had my period since i was 16 every 28 days like clock work , i once was prego but i last the maybe 4 months in.. that throw my flow off dor a yr then back to normal it was. but now its nov, 29.2012 & the last time i had a period was sept 16th this year, ive had spotting maybe a day this mnth when my period was suppose to come on the 16th, just for a few hours, and nothing else , I ve taken a dozen test and they all said (-) . so im confused on whats the problem or whats going on what should i do