HIV Risk with Oral Sex - CDC Info Question

Greetings. I had an encounter where oral sex was performed on me for approximately 10-15 seconds. I did not ejaculate in her mouth. I do not know whether or not the woman had sores and or cuts in her mouth. I had no cuts on my penis. I do not know the HIV status of the woman. I was tested 3 weeks after the encounter via blood draw which came back HIV negative. The CDC and Planned Parenthood sites seem to indicate that I was at risk for HIV infection. All the posts on here seem to indicate that I was at little to no risk. In your opinions, what risk did I incur (and why) and when should I be retested? Any information would be greatly appreciated.

[kumar007]

you never had a risk :0
oral sex does not transmit hiv...
your negative result proves that..
you never had to test to begin with and dnt require further tests