Morphine/breast milk

I had an ER visit today and they gave me one dose of morphine in my IV. They told me to pump & dump until 3 hours later and then I’d be fine to nurse but that just seems so quick to me…? I got discharged and pumped and dumped (11 ounces 😭😭😭) and gave her some milk I had saved in the fridge but I’m all out now. It’s been 6 hours since the dose.. any nurses on here that can reassure me? I ended up calling the hospital to talk to labor and delivery and they said I didn’t even need to pump and dump at all and that one dose was fine so idk why I’m still feeling weird about it. I guess I need to be reassured some more?? 😩😩