Honestly, I would at least talk to a radiator shop. It could be something as simple as a flush, but could be a bad sign of a head gasket leak. Many competent shops can take a quick look at the symptoms and give an adequate diagnosis.

I would have the radiator inspected, flushed, and rotted out by a radiator shop, check the engine codes to see if anything is wrong with the coolant temperature sensor (and possibly other things), then change the thermostat and t-stat housing gasket. Inspect all radiator lines as well. Be sure that a precise 50/50 mixture is achieved when the radiator is refilled (Prestone sells a very cheap tester).

I recently went through the whole coolant problem fiasco with my car, and things seem to be on the up now (knocks on wood). Good luck.