I had internal anal hemorrhoids(painful).how long until they completely heal?when can i have anal sex with my partner? there's nearly no pain

A few days to weeks: Hemorrhoids can take anywhere from a few days to a couple of weeks to heal, and I'd say once they stop bleeding and cease being painful you can resume anal sex with your partner. If the hemorrhoids become thrombosed (get a blood clot within them) it can take up to 3 months to heal on their own and more intensive treatment may be necessary.