I am 26 years of age. i recently had my period and had unprotected sex with my bf on the 3rd day of my period. i took a plan b on day 5. however, 5 days after my period ended i am now experiencing bleeding 2 days now. what is the cause of this?

Plan B affects your hormonal level and typically the sudden increase in hormones from the pills with the sudden drop in hormones just afer taking the pills is what causes you to bleed after plan B and hence prevent a pregnancy from continuing. However, when this bleeding from the plan B pills is variable when it occurs because your own production in hormones influence the situation as well.

Plan B often causes a little bleeding several days after it is taken and this might even be more suggestive that it is working. Sometimes a little bleeding occurs mid-cycle and is associated with ovulation, but the timing as described does not sound quite consistent with that.