27 weeks, 3 days. Having really bad circulation problems.

I went to my ob yesterday and talked to her about, she told me to add a bit more salt to my diet and add electrolytes and about a cup and a half of coffee a day but im not sure this will help what im dealing with.

My blood pressure is always pretty low 98/60 - 108/70 at my lowest check it was 90/53. Almost everytime i stand up i get extremely dizzy and have to bend over to keep myself from passing out, i get random STRONG palpitations that almost knock the wind out of me, sometimes my heart will start to POUND out of nowhere and i feel like i cant catch my breath, and i have almost zero energy. I am trying all the advice from my doctor and hoping thats all i need but,

Has anyone else dealt with something similar? What helped? What turned out to be the cause? Because everything im finding is pointing to POTS syndrome.