Sounds like the heater matrix is leaking, or either the flow or return hoses are leaking,
maybe one of the hose securing clips is loose,
as the pressure rises in the cooling system, coolant will be forced out from the leak into the cars interior front footwell,
Keep your eye on the coolant level and top up frequently,
I strongly suggest locating and fixing the leak asap.
Don't use the car for long journeys.
paul
February 2012