popscene01
I’ve always had problems with dark circles. The best that has worked for me is a primer (Sephora perfecting eye primer or their anti-shine foundation primer is good & cheap) then the BEST cover up w/eye primer I have was with the Kat Von D High Voltage Eye primer. I use it above & below my eyes for the dark circles. If the shading doesn’t blend well with the skin tone, then use your regular foundation on top of that, then I use powder for matting.
It can be time consuming but I would suggest if you have a Sephora or Ulta close to you go in & ask someone to help you & try the stuff out. (Sephora peeps seem better at makeup consults to me.) Little bit can go a long way so they have been worth the $ to me.
I’ve noticed after my TT the circles seem darker also. I really don’t think it has to do with my TED. (Karen, I’m the same way w/my TED) The circles could be from allergies, eczema, thinning skin, rubbing your eyes. So… maybe it could somehow be brought on by the disease. 
Know all too well about the “Are you ok?” My supervisor would ask me EVERY DAY and I gave him the same answer EVERY DAY. 
Good luck! Amanda