This is great news. It suggests that the tingling you are having is not related to herpes. I think it would be OK to have sex with all the precautions but you know that nothing is perfect, right? I think the thing is you’ve done everything you can.
It is good to take the meds about 12 hours apart but it does not have to be exact, no. This medicine is approved for once a day so twice a day is even better and especially if taken regularly.