About a year ago i started to get pain when i had sexual intercourse, it is unbearable pain and is very embarrasing. Its got to the point where i cant have it because it hurts too much! i also get stabbing pains up my vagina and sharp pains in my lower stomach area at both sides, my periods range from 20 day cycle to 26 days cycle, its horrible as i dont get any signs of when im going to come on, all of a sudden i will feel the blood coming out! ive been to the GUM clinic and have been testsed for all the STI's and AIDS and its all come back fine. Im really worried and dont know what it could be! Please help me someone.