Nazir 46: Nezirut and Impediments to Completing It

A mishnah on the process of the sacrifices; A nazir who cooks the shelamim sacrifice, or overcooks it, and the kohen takes it with the unleavened bread, and the nazir waves them around, after the kohen puts it on his palms, having already shaved his head. And then the Gemara brings in additional machloket to understand the importance of each stage - would not waving cancel the nezirut? The korbanot? But what about how shaving doesn't cancel? Or what about a bald nazir? Plus, another mishnah on the procedure of bringing the sin-offering plus shaving, and what happens if things were done out of order, for example.