I was wondering if you could help,

I have had pain for a few months when I go to the loo, I have been to the Doctor's and had antibiotics as had a urinary tract infection, this didn't clear it, i went back to the Doctors as I still have the pain only I was told that there was nothing wrong and the infection had passed.

Sorry to sound crude but the only way I can describe the pain is, it hurts when I open to pass water, then it stops whilst i do, and after i've finished it hurts again.

Any siggestions/Solutions?