Possible blown head gasket?

I'm pretty sure I have at least blown my head gasket, if not worse. I was pushing my engine pretty hard going 80 MPH uphill when the engine quit. I placed it in neutral and tried the restart the engine. The starter would crank, so I coasted to a stop. Lifted the hood and found milky oil all over the passenger side of the engine. It seems to have blown out of the dipstick tube. I check the radiator and it was significantly low as I expected due to the milky oil. I am guessing head gasket failed which allowed coolant into the crankcase and blowing the oil/coolant mixture to spray out of the dipstick tube. I am planning on replacing the head gaskets but wanted to see if I might be missing something in my diagnosis. How likely am I right and am I missing something else which could have happened?