I had sex the day my period stopped and took plan b the same day. I had bleeding a week later for 3 days, and then had my regular period relatively on time few weeks later. A little over a month later I have a yeast infection. Could it be from a hormonal imbalance? I also recently used a bodywash that caused an allergic reaction to my skin. I also washed my vagina with that soap. I'm not sure which one the yeast infection is coming from.