Valtrex ?? How long did it take to kick in // HERPES

I’ was prescribed Valtrex 500mg , I’m in so much painnnn the sores hurt like hell making me walk super funny ! The doctor at the Er prescribed me Valtrex because my open cuts sores looked like it could be Herpes but by them being a ER they couldn’t test me for that ! I had to see a OBGYN BUT she just went and prescribed me Valtrex just Incase to treat me ! But my question is HOW LONG DID IT TAKE ??? To kick in !!! I literally can’t sleep at night orrr pee right 😩😩