Low Coolant Light On

I have a 93 lumina 100,000 miles.... I only know the basics about cars. My "low coolant light" keeps comming on. Yesterday it was only blinking on and off, but today it stayed on the whole time i was driving. I checked my coolant level and it was fine, but dumb me added a little more anyways. I also saw what looked like water comming out from under my car. I of course called my father and he said it was probably the AC dripping water since I live in florida and the AC has been running a lot lately. However, that doesn't explain why my coolant light wont go off, even though it looks full. Should I be worried? and what do you think it may be?????

Please respond back in laymond terms because i don't know much about cars.

ANY HELP WOULD REALLY BE APPRECIATED!!!! I run a very buisy schedule going to college, and am just curious on how serious and necessiary it would be to get it to the shop right away.

THANKS SO MUCH!!!!!

It could very well be just a bad sensor. The sensor is mounted on the passenger side of the radiator, near the top. The water is probably just that, water. Coolant is green (I think on these cars), and smells strongly of....stuff :P

You may want to look into repair/replacement of the sensor. Its probably about time to have the cooling system flushed and serviced anyhow.

My take on this is the fact that you said you added coolant. Where I come from, we always mix our coolant half and half with water. I'm not sure if this would trigger a low coolant light though. I would actually myself take it to the shop, and have it flushed, and refilled. and I also do know that there should be an overflow hose somewhere, and that its not a good idea to over fill your coolant. Also make sure that when your adding coolant, your not just adding it to the overflow tank. try checking the level of coolant directally in the radiator. There might be a bad hose between your tank, and radiator. Who knows. Good luck

This happened to my '90 lumina recently. Try checking this if you haven't already figured it out.
(Ok, this is actually just a more detailed set of instructions for doing what tblake suggested above)
FIRST; (I put this in caps because it's really really important,) let the car cool. Overnight is best.
Second; After it's cooled off, pop the hood without starting the car up.
Third; Look for the cap that accesses the coolant hose directly. On the '90 Luminas it's on the left hand side right up at the front of the car. It will be a cap that says "Do not open when hot" If you do so, the coolant may be under extreme pressure and can explode out when you open the cap. This won't happen if the car is cool.
Fourth; Pop this cap open. You should be able to see coolant, and a little bit might even spill out. This is good. It means that your reservoir is filling the lines properly.
Also, there is a way to check if the liquid dripping from your car is coolant, water, oil, transmission fluid, whatever. Just take a piece of white cloth or paper (paper towels work really well) that you can throw away. Soak up a little bit of the dripping stuff. Against the white you'll be able to see what color it is. If it comes up that bright yellowish green of coolant, you've got a leak somewhere, and should have the hose checked and replaced. (In my car the hose was metal and had rusted all the way through.) Red is transmission fluid, brown or black is probably oil (or really old, used transmission fluid) Clear is probably water.