Hi, Thanks for using HCM.
Break through bleeding are common will hormonal
pills. as you had reddish discharge which could be due to hormonal pill you have taken.
As you have taken emergency pill with in 72 hr, helpful in preventing conception. but chances of pregnancy
can't be ruled out.wait for your periods to start, if get delayed by a week or 2 need to get pregnancy test done.
Regular use of emergency pill is not advised. Better to use barrier method or hormonal pill depending on your need.
Hope this helps you.