2000 Pontiac Grand Am loss of all coolant all at once

Ok here are the symptoms. Shortly after driving the car, about 1.5 miles, the temp gauge went about three quarters of the way up then back quickly back down to proper temp. Then shortly after that all at once all of the coolant spilled out of the overflow tank release hose, (not positive of what its called but its the hose not connected to anything and just goes to the ground when the coolant level is too high) but in this case almost all of the coolant is being expelled out of this hose. Obviously when this happens the car quickly overheated. I added coolant and was able to get it home without it overheating again no positive signs of a head gasket i.E. Fluids mixing, white smoke etc. Although I guess I can't rule it out.I'm thinking possible clog in the system, air pockets because I did recently change the lower radiator hose although I tried bleeding the system and it seemed to have no effect.(Assuming I did it right) oh and even when the overflow tank is full the heat in the car is sporadic. It will work fine then go freezing cold (in the summer) I'm just trying my best to diagnose the problem from the safety of my garage before deciding whether or not its worth paying for a tow as opposed to driving it too the shop about three miles away. Any help would be greatly appreciated