Trust his diagnosis. Bumps with follicles around them are folliculitis, the result of heat and sweat.
I don't know where the internet sites you read come up with the statement that itching and discomfort or no symptoms at all are common in herpes. To diagnose herpes there have to be blisters, at least sometimes. In between attacks there may be no symptoms, but there have to be blistery attacks for there to be a "between" period. You never had an attack.
As for itching, people itch in groins all the time. Thinking you have herpes can certainly make you itch.
Hepres blood tests aren't much help, because having herpes antibodies in the blood just means that the herpes virus affected the body sometime in your life, but jot necessarily genital herpes.
I'd suggest avoiding unprotected sex. The post-sex anxiety just isn't worth it.
Take care.
Dr. Rockoff