1994 Pontiac Firebird Engine Running HOT!

Engine Cooling problem
1994 Pontiac Firebird 6 cyl Automatic 150xxx miles

I bought my Firebird almost 2 years ago. Inbetween that time I have gotten the trans rebuilt and many other things replaced. Last summer I had gotten the water pump replaced due to a mechanic telling me that I had an anti freeze leak in my water pump and he put some stop leak in there that caused me to have other problems to go wrong with my car. The bad thing is I didnt know I had stop leak in my car until I went to have the car inspected due to the antifreeze leak. I get the water pump replaced, and then I had recently gotten a new radiator and on my reciept it says that I have a blown head gasket. My car doesnt smoke white or black, it doesnt smell, and as a matter of fact it actually runs like a beauty. But its still runnin hot after I gotten the water pump and radiator replaced. I have a new heater core as well. So now I am trying to figure out why is my car still over heater like this. I am hoping after the thermostat have been replaced that the car goes back to its normal self. But I cant see it being an head gasket because there is nothing out of the norm right now.