Do a pressure check on the radiator. If it's your headgasket, and you're driving it like that, you could be in for more than just a headgasket replacement... you could blow your radiator and some other bad things.
As said by somebody else, headgasket doesn't always mean water to oil, it can also be oil to engine and water to engine.

Get that checked out, if it's headgasket, bad luck.