When to worry about being Anemic?

I went to the doctor and found out that i was severly anemic, this was about 3-4 months ago. I started taking a vitamin every morning, but i felt sick everytime i took it, like it took everything i had not to vomit every morning! I stopped taking the vitamin about 2 weeks ago and i still have a nausea feeling and i don't have any energy, and i have constant stomach aches. Am i ok? or should i be worried?