Did the right thing by bringing evidence of ties to home country (property abroad), temporary nature of visit (wedding invitation) even if they failed to look at them.
Would NOT say you did the wrong thing by withdrawing request for admission; no long term harm here where if you don't they can put you through "expedited removal" - quick, at-the-border deportation with five-year bar to coming back.
Would NOT try to go through different post, all info will be in computer PLUS it will look like you are trying to avoid last post and arouse further suspicions.
Consult an immigration attorney to assemble best overall evidence of ties to home country/commitment to return, gather evidence that info cited by officer(s) was incorrect (your own medical report saying no problem with mental state plus evaluation here if you have it, and evidence/documentation that time here was nine years ago and non-work).
Link: below, the Traveler's Redress Inquiry Program, to address "bad" info in the DHS computer system and keep people having the same bad experience over and over from having it. Take a look and once you've consulted a lawyer and have all your info together consider using the program ( a lawyer may be able to help with the application).
Consult an immigration attorney just as Mr. Reich observes.
Good luck to you.
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