I might have low Iron?

I think i might have low iron. You see i didn't eat much meat for a long time i dont know why and lately i have been feeling weak and tired while urinating every 1-3 hours. I also have a pain in the right side of my belly button. I have constipation sorta. Are these signs of low iron? Even the urinating part. Also i ate some cow liver ( Yuck ) and i felt a bit better so i think i do have low iron.