its been 77 days since my last incident with a prostitute-unprotected oral sex. around 60tth day, i had developed sore in my penis along with itching all over the body and recently by 70 th day, i had severe anal[rectal] pain which seems to have a red scratch kind of mark in rectum in addition to sore in my penis. tested negative for syphillis and hiv on 37th and 77th day using tridot rapid test.unbearable pain in rectum region for more than a week. is it hiv or some other std.