I am 18 and just moved to New York City to attend college about 3 months ago. The last real period I had was the week before I moved(August), then I missed my next period(September). The next month(end of September) I had sex, but took a morning after pill; I have taken the pill before, and that really delayed my period. I still have not had my period(Middle of November). I took several pregnancy tests but all of them were negative and I am not showing any signs of pregnancy other then my missed periods. I am wondering if it is common for a freshman in college to have irregular periods like this? These past months have been very hard emotionally for me because I left all of my friends, family, and boyfriend when I moved, and my college life in NYC is so much different from my life I had back home. Could I just be having irregular periods due to emotional and physical stress?