The blood pressure that you have developed is different from normal blood pressure ehich is basically a blood vessel problem so you have to take medicine life long. Post pregnancy
Ht is called as Pre-eclampsia. It is related to pregnancy and after the pregnacy subsides it will also dissappear. So you have to follow up with your gyneacologist for 3 months and most probably by that this time he will tapper your dose and stop medicine. If your doctor forund the bp still remain high that means you are having a normal HT for which you have to take lifelong medicine but you don't belong to those group.