Can this cause a high heart rate?

Hi so I found out I am severely iron deficient. Which is causing me to become anemic. My hemoglobin is going down every few weeks. I’m pregnant so that could be why. I see a hematologist next week (they seem to be very concerned about me which is kinda scaring me). But my heart rate while resting will sometimes go up to 134. And standing is a whole other story. My OB knows my hr is high. As well as my cardiologist. He says everything looks fine and sounds fine just have a high hr. This all started when my hemoglobin started to drop in October. Which is why I’m wondering if iron deficiency/anemia can cause a high hr?? I also just started iron pills but keep throwing up from it. So I am taking it every two days cause I really don’t know if I can throw up everyday from that pill. It makes me feel miserable!