Hi, I was diagnosed with low iron levels about three months ago after trouble with my vision on day. I hae been taking ferrous gluconate and have been conscious of my diet and what I eat. As of late I am waking up with intense headaches and feeling quite sick. The other morning before work I had that feeling and all of a sudden my heart started racing and my body started shaking for a little bit. It scared me a lot. I feel terrible this morning once again.