Will someone experiencing their first herpes outbreak always have flu like symptoms?

No, not at all. Many first herpes infections have no headache, fever, muscle aches etc -- just the outbreak itself. It depends in part on prior infections with HSV. Some apparent first outbreaks are actually the first recurrence of a longstanding infection that previously caused no symptoms. Also, someone with previous HSV1 usually has less severe first infections with HSV2.

First time outbreak symptoms are fever, body aches, and swollen glands All are considered flu like symptoms.