Iron overdose?

Has anyone ever taken too much iron without realizing? I am anemic, so I take iron supplements along with a prenatal vitamin because I am TTC. I recently stopped taking my normal iron supplement and started taking Geritol instead. I didn't think anything of it because my doctor has never told me not to take my iron with the prenatal vitamins, but I have been taking almost 3 times the daily value for probably 2 weeks now. TMI, but all this week my poop was really, really dark, which I know is caused by iron. Then I started getting horrendous back pain two days ago and came to realize that it was from constipation. I was puking all morning yesterday and the constipation lasted for two days and last night I finally took some laxatives. I'm fine now, but concerned because I feel pretty crappy.. Sick wise. I have read all about iron poisoning and overdosing and it's pretty serious. Like, it starts with vomitting and tummy issues and then kind of goes to liver failure. I'm borderline freaking out but I cannot go to the doctor because of lack of insurance at the moment. Please help!