Thanks for your inquiry. I would also rather think that anxiety may be what is making these symptoms appear and persist. All the necessary tests have proven you are negative to HIV so you are indeed negative. There is nothing to be worried about. Go ahead and live your life to the brim.
Just to clear your mind and have a feel good factor, go through a good all-round STI therapy and get the emotional balance right and I am sure all would be well with you.