Hi Sillybrain (love that name)
The symptoms you describe sound like PCS although I'm not a doctor and several PCS symptoms overlap with other causes.....but that being said, it sounds like PCS.
You are lucky that your headaches have improved. I have been really struggling with dibiliating tension/migraine combo for months. I go tomorrow for the botox injections to see if they help alleviate the Migraines.
Fatigue is also really bad for me, but it is a combination of the medicine I am on as well as not being able to sleep at night.
You might find that your symptoms improve some, then seem to worsen after strenuous activity....that is normal. But it's great that you are improving!