Multiple rapid test HIV test

Hye guys, I have had 4 multiple rapid HIV tests..

1. 16/8/2012 - eztrust hiv antibody test (finger prick)
2. 5/10/2012 - oraquick hiv antibody test (oral swab)
3. 26/12/2012 - oraquick hiv antibody test (oral swab)
4. 26/12/2012 - immunochrome hiv antibody test - russian product (finger prick)

All came back negative. But sometimes I worry that the devices might be faulty or I performed the test incorrectly but if the C line appeared, u know that your tests are good.. My last exposure was on september, 2011..

However, I have this progressive oral hairy leukoplakia that has been going on for 6 months..

Are my result conclusive? Or should I do more tests??

[Teak]

http://www.medhelp.org/posts/HIV-Prevention/conclusive-HIV-result/show/1830454#post_8447893