Temperture Guage! Overheating now wont start!?

Hi guys, i brought a vauxhull corsa merit L reg 1996 i think it is, basicially it started overheatin jst after i brought it n recently it got 2 a point where i was drivin n it just went dead, i opened the coolant water thing, n it just over flowed like u wouldnt belive n now it just wont start the water coolant just drains the water but i dnt know where it is going as their is no leak under the car, the fan dnt kick in or anythink, i went to kwick fit n they said it sounded like the head gasket had gone, but i have looked in the oil thing and i cnt see any water in their or white froth in it.