Tension in Head 5 Days Post Botox?

It is more likely that the headaches removed from the area of treated crows feet are unrelated to the botox. See your doctor to determine if there is a reason for  your headaches such as sinus congestion. The forehead area can have headaches when the forehead is injected and sometimes that's related to technique and other times it can be a side effect which may last a few days. This is not to say that the Botox didn't cause your headaches, and you should discuss it with the doctor who did your treatment.

I have had patients complain about a mild headache after Botox treatment, but it is rare and short lived.  As Dr. Campanelli notes below, Botox is FDA approved to treat migraine headaches.  I have had some patients come in to have their Botox more to treat migraines than facial rhytides.  If it feels like your sinuses are blocked, you might actually have a sinusitis. Headaches are not an uncommon symptom of chronic sinusitis. I would recommend you have this evaluated by your internist or family practice physician. I have provided a link on sinusitis.

Botox has been FDA approved for the treatment of migraine headaches.  The exact mechanism is not well understood.  The likely reason is relaxation of the muscles as they wrap around the nerves.  In a small number of patients, the injections will trigger headaches.  This is self-limiting and of no medical concern.  If the headaches persist, a consultation with your primary physician is recommended.  The headaches may be unrelated to the Botox injection.