I'm sorry you are having trouble believing or trusting the replies you had from Dr. Hook in your thread a few weeks ago.
As he said in his last comment, "At any time beyond 4 weeks, the results of 4th generation tests for HIV are conclusive and should be believed."
1,2) The amount of risk from your exposure is meaningless. No matter now high the risk, and no matter how typical symptoms might have been, your tests show you were not infected.
3) It doesn't matter.
4) This has been answered repeatedly in your other thread. For still more information, read the thread linked below, and the other one linked there:
http://www.medhelp.org/posts/show/1891685
You do not have HIV. Believe the tests and accept the scientific evidence and the reasoned reassurance you have had repeatedly. There will be no more discussion on this thread.
HHH, MD