Did I commit Kufr?

Assalam Alaikum, I am very worried that I have committed kufr and please help me and clarify. Namely, I started to learn Arabic little by little, because I have a lot of problems with my pronunciation and I want to know what I am saying when I recite the Surah. My friends (among whom there are also Arabs) often make fun of me when I repeat the words "out of the blue". It doesn't bother me and I often say something on purpose to make them laugh. However, tonight, while I was fooling around like that, I looked at my friend for a moment and said: "Qul ya ejuhel kafirun", knowing (consciously or subconsciously) that there was a possibility that they would laugh because it was out of the blue. They laughed and it immediately occurred to me that I might have committed kufr. I did not intend to make fun of the words of Allah Almighty, but I am afraid that there is an element of "joking" in it. I never said it with the intention of infidelity, but I knew they might laugh. I really don't know why I said that. I feel very guilty. I became very depressed and went home, took a bath and said the shahada again. After that I read that one must take a bath after the shahada. I didn't do that, because I didn't want my family to get suspicious and because some scholars say that it is not mandatory. I started my fast, made wudu and prayed fajr. I am very worried: did I commit Kufr in the first place? If yes, have I done the right thing and is my fasting and Salah okay now? May Allah reward you for your work.