Difficult to say without examination. An abscess, STD, or other infection is certainly possible.
You can send off the white substance for a culture to see what kind of bacteria or yeast grows from this.
Urine tests and a urethral swab can be obtained to evaluate for a UTI, gonorrhea or chalmydia.
I would suggest an evaluation by your personal physician or a referral to a urologist.
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.
Kevin, M.D.
http://www.straightfromthedoc.com