You have seriously overreacted to a minimal risk situation. Your actions, especially in your inappropriate
treatment with
valacyclovir -- which did absolutely nothing to prevent herpes but, as you suggest, could interfere with finding out whether you were infected.
I would estimate the chance you caught herpes form the exposure described as well under 1 chance in 1,000, maybe as low as 1 in 100,000. It was wrong of your doctor to agree to your reqeust for valacyclovir treatment.