Pfff. I hope you got lucky there, man! I fully agree with Eftheeoh. The light is there for a reason! If you turn on the heater an no heat appears, that should make you even more realize that there is something wrong. I'd put my money on a broken waterpump...
Next time, at least stop to have a look under the hood. I can't believe you took the risk of a $3000-4000 repair for not wanting to stop alongside the road.
Fingers crossed you didn't bust your head gasket!