I taking ferrous sulphate bp 200g tablets, three times a day. I has a blood count of 9, my b12 levels were normal. I was feeling weak and tired and needed to sleep in the afternoon, I have been taking the tablets since last Friday. I feel less tired but in the last couple of days have begun to have thumping headaches which last for a few hours. Today the headache is less. My mind continues to feel sub par. I know I'm not thinking as clearly as I should be. I think thoughts and forget them easily. I find it difficult to regain the thread of what I was thinking about.

May I ask if this is normal.