Parasites and Testing.

I am 28 and have no children.  I do tend to be a hypochondriac and fear parasites.  A month ago i had some rectal "twinges"-- not exactly itching... but a creepy feeling.  I became paranoid that I had pin worms and took Pin-X once and again in two weeks.  Well, it has been two more weeks and i am experiencing the "twinging" again-- and i am nauseated.  I am not having any other gastro problems...  I have had to take two rounds of anti-biotics during this time -- amoxicillin and ceftin and now cipro-- for ear aches and a UTI.  I am afraid my UTI could be caused by pin worms since they really didn't find any bacteria in my urine... i just kept itching and itching where you urinate (this is not vaginal).. and they gave me the cipro to shut me up.  do you think someone my age with no children who rarely leaves the house would have pin worms??  should i take pin-x again?  i am NOT GOING to the doctor over this.