Is intentionally joking with laughter and interrupting prayer due to obsessive thoughts, for fear of friends gloating, considered disbelief?

If thoughts are mere fleeting notions that the heart does not settle upon, the Muslim will not be held accountable for them, as the Prophet (peace be upon him) said: "Indeed, Allah has forgiven my Ummah for whatever they whisper to themselves, as long as they do not act upon it or speak of it." However, one should turn away from them and not dwell on them. As for prayer, it is not invalidated by such notions, and it remains valid even if the heart is preoccupied with other things during it. It is forbidden to interrupt an obligatory prayer except out of necessity.

It is advisable to turn away from obsessive thoughts (waswas), to seek refuge in Allah from Satan, to regularly recite the Two Protectors (Surah Al-Falaq and Surah An-Nas), and to frequently recite the Quran and engage in the remembrance of Allah. The Prophet (peace be upon him) guided us to cure waswas during prayer by seeking refuge in Allah from the accursed Satan and spitting lightly to the left three times. The worshipper should also bear in mind that they are standing before Allah, conversing with Him, in order to achieve humility (khushu').