What do you take for your hypertension if you also sometimes go low in bp?

Maybe nothing. The goal in hypertensive treatment in pregnancy is not to get the BP as low in the normal range as possible. The goal is to avoid wide fluctuations and peaks that are potentially harmful. If the treatment is causing too low a bp, perhaps consideration should be given to reducing the dose or trying lifestyle changes (bed rest, for one) ins tread of higher dose meds.
BP up and down Rx. 43F asks What do you take for your HTN if you also get low BP? You need to take your BP daily till you find best combo of drugs and diet for you. Everyone is an new experiment in getting BP regulated at a healthy level. If you are not DASHing (doing the DASH diet) then start tomorrow. Your BP will likely be a lot better in 2 weeks. Some may need to take BP pills 2 x a day rather than once.