Plan B While Breastfeeding?

I am 3 months pp and my hubby and I had sex last night. The condom broke, so now I’m debating taking a Plan B. I am exclusively breastfeeding and have not gotten my period yet. I’ve read that if you are nursing at least every 4 hours, then the chance of getting pregnant is low. However my baby sleeps through the night. Like last night he went 9 hours between feedings.

Anyway, I know Plan B is safe to take while breastfeeding. My question is whether or not my baby can continue to nurse as usual after I take it, or should I pump and dump (or save for a bath) for a certain period of time after? TIA!