how did a stranger find out my identity through the internet?

[Carly]

through specifically yahoo/flickr

I am a yahoo answers/flickr user. this happened to be even though i did not use my real name or give out any private information. my real name isn't in my yahoo email and i use a different email for facebook and everything else.

how did a stranger find out my real name, assuming he/she can only find it from my yahoo/flickr information?

i never speak to strangers on the internet

I am a college student living on a college campus.

thanks!!
my real name isn't carly. this person knew my real name