Your car overheated twice and both times you added water. Is that
correct. Now you are saying the car will not turn over to start? Was
there any noise the engine was making before you added water and or
shut it off and can't get it going again? Have you tried a jump start?
That may explain the battery issue. Normally the battery and
overheating is not connected. If the car will not turn over at all, it may
indicate a safety switch has been activated to save the engine and
needs to be reset, or you may have some engine damage. If a jump
start will not get it started, you may have to have it towed. Do you or did
you see any radiator fluid under the car? Check the oil by pulling the dip
stick and if it is milky white, you have either head gasket leaking or a
cracked head. If not, and the jumpstart will not turn over the engine, it
may be internal issues. If the car turns over but not start, it may be
computer related. Either way a trip to the garage is in the near future.