I hear you about the teeth, Bud. I had all mine extracted 3 weeks ago, but am post treatment. I'm surprised they would start treatment so soon after the extractions. The usual wait time is 3 weeks, although some say 2 werks is sufficient, depending on healing, and some as short as 7 days, if it's needed, but a course of antibiotics may be given then, and healing should be done by the time radiation effects, 2 weeks, begin to occurr. This is not only to prevent infection during treatment, escecially with chemo, but ORN, Osteoradionecrosis later on.
Glad you have a caretaker, and shouldn't worry about being a burden. Take one day at a time, and do what you can. Everyone is different. It also depends on the extent of radiation, dosage, locations, if having chemo concurrently, and other factors.
Good luck