Bienvenido al foro. Pero Dr. Jose no responde aqui -- solamente en el foro internacional por HIV.
But I think I understand your question and can help if you understand English, or if someone can help you translate. (Siento que no puedo responder completamente en espanol.)
Every kind of HIV test is 100% accurate if done more than 3 months after the last possible exposure -- and with rare exceptions, by 6-8 weeks. (For more detail, see this thread:
http://www.medhelp.org/posts/show/1704700.) Your negative result 6 months after your last possible exposure is 100% reliable. There are no medical conditions or external factors that change the reliability of the test.
White coated tongue is rarely due to candida (thrush). And even if you really have oral candida, it isn't due to HIV. The HIV test results overrules all symptoms and exposure history. Coated tongue is common with many minor health conditions. If it continues or you remain concerned, see a doctor. But you should not worry at all about HIV.
I hope this has helped. Buena suerte-- HHH, MD