Why don't you conduct a simple Google search or perhaps get a clue?
Do you mean 6,000 years ago when people and dinosaurs roamed together? Yup, CO2 levels are now higher than they were since the dinosaurs roamed the earth. Of course, if you did just a little research or even read the article that I posted earlier, you would see that the levels remain nearly constant and in balance up to the industrial revolution (do you want me to research "industrial revolution" for you, too?), then they started to rise steadily since then.
Natural CO2 is not a problem but the questions is whether the industrial CO2 is contributing to dangerously high levels -- and are the high levels having a negative effect on our health and environment. If you believe that humans did well when they roamed with the dinosaurs then there's nothing to discuss. If you think that humans did not live with dinosaurs and the situation may be different then maybe you'll want to look up the facts.