What Does Bleeding After Taking Plan B Indicate?

Hello.I have a small predicament. I got my period june 6. and it ended june 11. I had sex on the 15th and the condom broke. I immediately resorted to taking emergency contraception by taking Plan B. a few days later on the 20th, which was yesterday, I got my "period" Is it a side effect from the pill? or is it something else? Is it a good sign that I bled 5 days after taking the pill or should I still be worried of a possible pregnancy?
I also recently got birth control but was told not to start it until Sunday the 27th