What Causes Irregularities In Periods?

my period or bleeding is running for 9 days still now......i had this problem also one year ago.then my doctor gave me tranexamic acid and then normens tab for three months...after taking this medicines, i became perfectly ok....i had regular periods for 1.5 years till last two months ago...but last two months there was no period..it again became irregular...this month it started 1n 17 feb and still continues.....should i take the previous medicine again?? i am 26 years old and married