Unportected penetrative sex warrents testing. As you tested after 1 and half years after your exposure and came back negative, this means you do not have HIV. You can get your tongue checked from you local GP. You are good as far as HIV is concerned. Make sure to use condoms each time you have sex with a partner of unknown hiv status.
Thanks for a quick response at_ss. I saw my GP and they said if it didn't go away in a months time to go back and see them. It just worries me!!
White tongue can be caused because of common reasons like drinking less water, lack of sleep, stress. Get it checked and I am sure you will be fine :)
You do not have an HIV concern.