Weed and nursing.

Yesterday I had an operation done and was told to pump and dump for 24 hours so my baby doesn't get any of the sedatives they gave me. I am EBF. They drugged me up well and warned that I may have poor memory and decision making skills. Since I had to pump and dump and have someone else care for my baby anyways I got talked into taking a single rip off a bong. It's the first and only time I've smoked in years. (I did it away from the baby and went to bed afterwards) Now today I feel better having the sedatives out of my body (still pumping and dumping), but I feel so bad I smoked. I'm so scared that this'll hurt my baby. All that being said, how long should I pump and dump to keep my baby safe? Another day? A week? I have no clue, I just want to keep baby safe and never do anything so stupid again. I know it was irresponsible and shitty of me, so please no back lash. I know it's not safe, but the damage of me smoking is done and now I just want to know how to proceed with caution. Please if anyone has any KIND helpful information I'd love to hear. I'll pump for how ever long I need to to keep her safe, but also don't want to continue pumping and dumping if it's safe. Please help.