I was traveling in a bus. I recite "BISMILLAH". but some mistake occurred and I wish to repeat bismi. at that time I found out a lady sitting besides me, watching me. I suddenly embarrassed and act as I was singing a song. I pronounced some words like 'bi bi bi bis bis' etc. after that I understood that I am sinning. because I am making mistakes in the recitation of bismi. I immediately recited bismi. then my mind dwell in a thought that is the mistake in the recitation of bismi is an intentionally occurred sin? does it cause to change the meaning? I want to repent soon. but I couldn't do it. I trapped under the devil. I repented after 1 hour. how can I repent now? i know making mistakes intentionally in the recitation of qur'aan is an act which leads to apostasy. so what is the rule in my case?