When i'm on my period not only is my flow extremely heavy, there is usually a sharp pain and when i expel a thick, tissue (meaty) substance.

Heavy periods: Hello, It is not unusual for a young woman to have heavy, painful periods, It is not unusual to pass blood clots with a heavy flow and even tissue. This often points to an increased build up of uterine lining which the body has to get rid of. I would suggest taking the "pill" for cycle regulation. This should decrease flow and pain. The Depo-Provera injection is also good for cycle control.