My bp has been 97/68 and I have tachyardia but my bp has been low for two days now what should I do?

Salt and Hydration. If your health is otherwise normal and you are in the second or third trimester it sounds like you are having a physiological response to dehydration. You could eat more salt and hydrate with water and electrolyte containing fluids but I would check with your obstetrician first.