I had some symptoms like lymph nods or a kind of herpes on my mouth, my HIV test was negativ after more than 6 month of the risk but I am afraid?

HIV negative. Without knowing exactly what tests were run it is difficult to say for certain, but the overwhelming chance is that you are HIV negative. The lesson is obvious. Only protected sex and only with individuals you "know" well. You can never be sure of honesty when it comes to sex, money, politics and life. Appreciate your concern but think you can relax. Be well.