I think for a trip home you should be fine. But it is nice to have the gauge to back you up.

You do have a low coolant light in the car which will alert you to a leak if you have one, the cooling fans work and the water pump is relatively new and reliable. I wouldn't worry about much just for that one trip.

As you probably well know, when the water pump fails in our Duratecs, a common symptom was no hot air through the heater. The fact that you got the heat to blow suggests to me that it is not a water pump issue. In fact, I would say that either the sending unit is bad, or the wire that leads to it is grounding out somewhere causing the "overheat" indication on your gauge.