You have a bunch of threads here and everyone told you to get a duo test, so I don't know why they gave you the western blot. Is this the only test you had done?
Western blot is a confirmatory test for positive results on antibody test.
To help you understand further - Antibodies are your body's immune reaction to fight the presence of alien viral material. An antibody test looks for those reaction.
Western blots tests are also known as protein immunoblots. These tests are used to detect specific proteins in a sample. The basic technique of a Western blot is to sort proteins by length on a gel. Then that arrangement is laid out as a grid and it is subjected to antibodies that react to the specific proteins that are being searched for.
In case of Western blots that are used for HIV testing, this process is actually performed in reverse. Normally, in a Western blot test, unknown proteins are being searched for with known antibodies. However, for an HIV Western blot test, lab technicians work with prepared samples of HIV proteins and look to see if there are any antibodies in a person's blood that stick to them.
Undetected bands / Negative result on WB test is Platinum. If that's negative. You are Negative. There is nothing above and beyond for speculation. You do not need any more tests, this was the mightiest of all.