I haven't had my period for about 7 months, I went to the doctors and had an ultra sound, and a vaginal biopsy... they didn't find anything wrong (I'm 18 and there is no possible way of me being pregnant)... after 7 long months I finally got my period today, and my cramps are unbelievable as imagined. I'm also having a lot of blood clots... should I go to the doc again or is this normal?