Yes you were tricked.  And yes the polygraphers whole job is to obtain disqualifying admissions from applicants.  They are not there to "help you pass".  If you had been reading this site for as long as you say you have I would think you would have deduced that by now.

The reason I said you might not be cut out for police work is that you stated you read this site for months and the TBTLD yet you apparently still fell for the tricks polygraphers like to use to obtain confessions.  Sorry but to me that sounds like you can't absorb info or are relatively nieve.  Both traits that are IMO not akin to policing.  I fell for the same trick my friend so I am not calling the kettle black here.

Watch your back when appying to other forces.  Their application forms will ask whether you have applied elsewhere and for what reasons you were deferred.  They will contact the original force and obtain their reason, poly results and even opinions from the officers there for your deferral.  If the polygrapher fabricated a falsified confession based on your statements you can rest assured that you are likely not going to get hired elsewhere.

If I were you I would try my best to find out why you got deferred.  If it is the poly (that is providing they tell you the truth in the first place) I would request to have your video reviewed by the head of recruiting.  Clear up you poly DQ or you are shot everywhere else you apply.  It will haunt you and your future applications for ever.  IMHO.