So, the fact I woke with a head cold was met with resignation. Learned the word for this type of "sick" ("rhume" - think of Peter Sellers trying to say the word "room", and you've got it) and the phrase for "sick in the head" ("rhume avec maux de tête"). The chemist in Guingamp recommended a mix of Paracetamol (aches), Chlorpheniramine (nose), and Vitamin C (because it's "the fad"). Not sure the over-the-counter dosages are high enough to really help, but the three will be better at treating the symptoms than simple aspirin, which is what I brought with me.
And, for whatever reason, I couldn't find anything remotely close to these drugs in the relatively-large grocery in Bégard. It may be that I just didn't visit the right part of the store, or it could be against the law. If I'm lucky lucky, I'll awaken tomorrow without symptoms. If not, the following is important to remember:
"If you take the right drugs, you will be fine in a week. If you don't take these drugs, you will probably be better in seven days."And no matter, in seven days I'll be able to think of the word "symptoms" in ENGLISH in less than 3 minutes.