ESTRADIOL...SAFE OR NAH!?!

hello everyone! Just got my BFP days ago and went to the doctor to get my initial bloodwork done. They told me my Estrogen level was 175 and it should be 200 or higher. They wanted to put me on ESTRADIOL to raise my levels. I go to pick up the medicine and the pharmacist personally comes to the window and says you know this causes birth defects right?! And I said no I do not my RE prescribed it because she said my Estrogen levels were low. she said well you need to talk to your OBGYN. and i said i dont have one yet just my RE cause that was the last doctor I saw so I went back to her. she recommended I not take the medicine so I didn't. I called the doctor to tell them what the pharmacist had said they pretty much laughed and said no we would NOT ask you to take that if it was harmful. So I went back to get the medicine the same pharmacist was there warning me AGAIN. I told her I did speak with the doctor and she said it was okay and she still said I shouldnt take it!! What in the world??!! has ANYONE had any experience with this situation and medication?! i still am not sure if I should take it but want to do what I can to prevent a miscarriage obviously at all cost. PLEASE HELP!!!