Does Stopping Primolut Cause A Change In Bleeding Pattern?

Hi doctor, im 31 old lady, i ve 2 kids, i start taking primolout n to delay my period befor its date about 15 days, 1 pill/day , put i notice that i have a severe stomachache while im taking it and the pain increases every day so i stoped taking it after 5 days. The period comes after that in 4 days. But its not the same. Its very light (one time a day and stops untill next day). Im feeling confused and i dont know what to do: is that a period or not?? And is that normal after missusing the medcine?? And when i should expect it will ends? Tacking in mind that my normal period usually for 4-5 days. Please take care of my qeustion i realy need to know the ansewrs for relegouse reasons. Thanks alot.