Chevy HHR Network - engine light

Ok so I am driving down the road 2day and engine light came on. I pulled in to the post office i need to go there any how and let it sit for a lil bit so i could check all the fluids just to make sure. Well I figured i would bring it to dealer cause all fluids looked fine except coolant in the over flow tank. I bring it to the service guy and said what was wrong and he said well your over your warrentee i said i have the extended one he said ok and took the car to be looked at. Well 30 minutes later here he comes and tells me the light was on because of the coolant system and we need to watch it cause they didnt find any problems minus the over flow tank empty. I said ok. He says that the mechanic will bring it out in a few minutes 15 minutes later i walk out to the service area and there it is. So i walk up to the desk and the service manager comes up says yup all done and that will be 68 bucks. I said for what he was like for looking at the car its out of warrenty. I said no i have extended one he says it doesnt cover that stuff. I then say i was NEVER told about being charged and all he could say was i was told. Well i did end up paying it and now YELLING that they r a bunch of A holes lol and that i was leaving there and trading the HHR in RIGHT NOW and now i am going to call general manager 2morrow and ***** 2 him. thanks for letting me get this off my chest any one else ever hear of this ??????????????/