Is It Safe To Take Amlodipine Inspite Of Having Low BP Level?

I have been taking Amlodipine 5mg. At last MD visit, my BP was 108/70. My doctor decreased it to 2.5 mg. Last wek cardiologist ddtold me to stop it as BP was running much lower. It is still very low with constant dizziness. I called MD and she wants me to continue on 2.5 mg. Why/ I dai not get to speak to her.