Asalamualaikum, I am having really bad doubts if what i have done is backbiting or not. Recently, I have been thinking repeatedly if anything I am doing is backbiting. I got a tissue and was blowing my nose, some of the mucus went onto my finger. I then thought to lick my finger but I also thought that I would be backbiting on somebody while doing so. I then licked my finger anyway (I am pretty sure my intention was to backbite). After that, the person I was thinking if I was backbiting on them came. Please inform me if this would still be backbiting and I would have to apologise to them.
Salaam, I think you are overthinking it. You are not backbiting, and the fact that you are paranoid that you are, shows that you have a pure, clean heart. Remember that we all have thoughts and the shaitan always tries to make us act out on our thoughts. Always seek refuge in Allah (swt), and you will be ok. Remember, Islam is easy, and we make it difficult. If you backbite accidentally one day, just ask Allah (swt) for forgiveness, for he is the most forgiving, most merciful! Hope that helps. Indeed He is the most Forgiving, the Merciful' (Quran 39:53). Best,