ACHING TESTICLES/IMPOTENCE

My problems started just after taking two courses of antibiotics for a
severe mouth abcess.The main symptoms I encountered were:
Being unable to gain or maintain an erection, Total loss of libido,
Light headedness and disorientation.Stiff and aching neck.
I went to see my GP mainly about my impotence and libido problems and
he more or less dismissed it as being a psychological problem.My
problems persisted,so I went back to my GP to have my blood tested for
thyroid,testosterone,sugar,cholestrol which all came back normal.I also
had my blood pressure taken which was also normal.Throughout all of
this I have had a constant ache in my testicles,but my GP examined them and said everything was fine.He put me on a course of doxycycline because he felt there was a possibility there may be an infection in my epididymis,which proved unfounded because they appeared to make my symptoms worse.I now have an achy pain in my lower side which is becoming quite niggly.I'm not sure where else to turn.Do you have any suggestions?