You would show symptoms within hours or a day or two after experiencing this, if you are thinking this is prodrome. It's a different feeling for everyone - some get tingling in the area they get outbreaks, some get deep muscle pains in the area (like thighs or butt) - it really depends on the person.
If this has been going on for some time (and 9 months is way too long), then it's time to move beyond herpes as a cause, especially if you are testing negative. This could be anything from a pinched nerve to sciatica to an anal fissure, and you aren't doing yourself any favors by not examining things further to get to the cause.
im still asking the same questions ... i'v had tingling for nine months ... and my tests are negative ... im at a loss .... I hope you get a good answer from someone who knows and does test positive to verify the concern and condition.... best of luck ... take care