The chances are very low with condom use.
Even if you were in a long term relationship with someone who had hsv2, as a male, your chances would be 4% a year to get hsv2 from a woman who had it, provided you knew she had it, you avoided sex during outbreaks, and had sex 2-3x a week.
Your chances from a one time protected encounter are very slim.
I wouldn't worry at all.