No. Never. I’ve never seen anyone have that problem, either, unless it’s a typo.
I have gotten other words mixed up sometimes, though now I can’t bring any to mind, and also though I am a good speller I still make a few consistent mistakes (“sherrif”). For that reason I am largely forgiving about most spelling errors I see.
I don’t have a problem differentiating the spelling, per se. It’s the typing that gives me trouble, because my damn fingers will go on neurological auto-complete and type the word I use more often (“through”) rather than the word my higher cognitive functions are thinking (“thorough”).
I usually catch it immediately and berate my treacherous hands while correcting it, but it’s still a bit of backspacing and very careful letter-by-letter spelling to get it right.
I know automatically the difference between them but I have to take a bit of care when typing “thorough”. My fingers want to type “through”, probably because I use it more. Also, I swear that every time–without fail–I type “withing” for “within”. Muscle memory can be a little scamp sometimes.