are you allowed to cry because of how beautiful the Quran is?*(In Salat) because of how beautiful the signs and meanings are?
السَّلامُ عليكم ورحمةالله وبركاته
Crying in response to recitation does not invalidate Salah, it is actually desirable if due to fear and love for Allah. There is an hadith where the Prophet صلى الله عليه وسلم said "I have established palaces at the highest levels of paradise for those who shed tears and no one will share to with him."