Am I doing the spell check wrong?

It seems to have messed up a couple of things I have written.
A few days ago in the "free for all" forum, I posted reply #7. The second to last sentence in that reply was originally written to say in part, "...some people have wisened up and hopefully they will get..."
The spell check told me that I misspelled "wizened." I clicked on "change" and then posted. After I posted, I realized that sentence had been messed up. Both spellings were there and parts of "and hopefully" were deleted.
This happened again when I personal mailed someone, but this time I caught it and corrected it.
What did I do wrong?