How high should my iron levels be?!

I've searched all over the web for this, but I never find anything about the iron levels, just the hemoglobin levels, which I think are different. I went in for a blood test 3 months ago and they said my iron levels were 4, and gave me some iron pills. This week I went back again, and it had only gone up to 5. I looked those levels up, but it pretty much said I should be in a coma or something by now...as far as I know I'm fine lol.