1994 Ford Tempo Possible Head Gasket Issues

Engine Cooling problem
1994 Ford Tempo 4 cyl Front Wheel Drive Automatic

I have recently had a water pump, upper radiator hose and thermostat installed on my car. The car initially had problems overheating when before the water pump was installed. That only partially solved the problem. The car was still running hot, but it was the top part of normal and not technically overheating. My brother-in-law said that I needed a new radiator hose and thermostat. I go to drive the car after those were put on and the car will not shift when I drive. My father looked under the hood and the engine was steaming and there appeared to be water seeping out from the oil cap. I was told that this could possibly be a blown head gasket. Is this a good possibility?