Negative herpes and hiv test at 6 months after unprotected sex. is this conclusive?

Probably conclusive for both. However, more useful advice might be available if you would like to describe the nature of the exposure.

Testing 4-6 weeks after exposure is the normal time for results. Sometimes up to three months will give a positive, but after 6 months a negative is [positive] news. In future to avoid tests and concerns practice safe sex.