Ulcer or open sore on penis

Hi,
  I am a 21 year old male, and am concerned about what i think was an ulcer on my penis about 5 years ago.  I was in high school at the time and had not engaged in sexual intercourse. I had fooled around with one girl, who was also a virgin, but we didn't have sex.  One day i noticed what i thought was a pimple on my penis shaft, but it got bigger and formed an ulcer.  It didn't hurt and it went away after a few weeks and i forgot about it.  Nothing ever happened after that and i didn't think anything of it because i was not sexually active.  
  Recently, about 5 years later i have thought about it and i am really scared that somehow i could have an STD, even though i got this ulcer without having sex.  It sounds like the primary stage of syphillis (syphilis), i never had a rash on my body that is seen in secondary syphillis (syphilis) however.  I am now worried that it could be in a late stage and i could have serious effects.  
  I am now in a serious relationship, and have been for a few years.  I am sexually active, and i have had unprotected sex a few times. We were both virgins when we started dating.
  Is there anything else that could have caused what i believe to be an ulcer on my penis? I am scared that i have something serious that could be causing problems in my body.  Can you get an ulcer on the penis without sexual intercourse?  
Please help, Thank you!
Cman

[Kevin Pho, MD]

STDs such as herpes, syphillis (syphilis) or chancroid are possibilities at this point.  I would certainly be tested for gonorrhea and chlamydia as well.  

Test for herpes and chancroid can include a swab of the ulcer as well as blood tests.  A blood test can also be done for syphillis (syphilis) as well.  

Treatment would determine on what is found during these tests.  I certainly would discuss these options with your personal physician.  

I would also recommend condoms in all cases of sexual contact.

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.
Medical Weblog:
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