Prenatal Vitamins Question (:?

I had my first appointment today! I'm only five weeks two days so there wasn't much to see on my ultraSound but I saw my gestational sack and my yolk sack, and she said she saw a little flutter in my baby's heart! (since I'm still so early) Okay that had nothing to do with my question, I'm just so excited! Okay now about the prenatals. Is there a certain limit to how many you can take in a certain time? Like how you can only take 2 Tylenol every 4-5 hours? I read the back of the bottle and it warned about iron overdose. I took one around four when I got them and i planned on taking another in the morning (when I plan to take them everyday). But do I have to take them like 24 hours apart? Omg I'm ranting! Okay sorry (: Thanks for your help!