In addition to the chlamydia, I would also test for gonorrhea. The Azithromycin won't adequately cover for this.
I would also consider a digital rectal exam to evaluate for prostatitis - there are some cases that require an extended period of antibiotics.
If infection has completely been ruled out, a cystoscopy can be considered to evaluate for urethral strictures or polyps which can also cause penile tip soreness.
There is no specific time for the soreness to go away - this varies from patient to patient.
Followup with your personal physician is essential.
This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.
Thanks,
Kevin, M.D.