I suffered from viral meningitis but my doctor didn't say anything about a herpes. If I had gotten meningitis from a herpes virus...Would I know?

Maybe. Mollaret's is a viral meningitis that's often the result of meeting genital herpes; it may happen several times. A characteristic cell may show up in the spinal fluid. Your physicain may have considered this. If you do not have herpes elsewhere, this is unlikely.