Nick, you are 100% right!
When I got my second concussion, I felt miserable, had difficulties accepting the situation, felt depressed - you know all those "wonderful" feelings. Plus, a horrible headache didn't add any optimism...
Anyway, after two weeks of being miserable, i decided to get up and do something, since I'm miserable anyway. So, I went shopping and helped my husband with painting walls later. What can I say? The first day was pure HELL, but second day was better, and I felt 100% myself in 4, maybe 5 days (it was a while ago, so I can't remember). Of course, my concussion was mild an there wad no visible brain injury, but still...
Well, I've been reading your posts and I'm glad you're feeling better! Hope, it's something that will last