I got my period five days late this month and then only bled for one day. Tired, sore, tender, head aches, sick to my stomach. What could be going on?

Could be. pregnant in spite of having one day of bleeding. If pregnancy is not a possibility, then you would consider other causes such as viral illness for example. Wait a week and do a pregnancy test if your symptoms continue. See your doctor if not pregnant and you are not getting better.