Thank you for your important question.
May Allah, Most High, reward you for your desire to increase in knowledge.
- Unintentionally mispronouncing a letter or two does not nullify your prayer. Your prayer is valid.
- Reciting the incorrect word in a verse and then returning to correct it does not affect the prayer’s validity. Your prayer is valid.
(Ibn Abidin, al-Hashiya)
Before beginning your prayer, consider reciting the ta`awwudh (I seek refuge in Allah from the accursed devil) and make a short supplication to ask Allah to free you of misgivings.
And Allah alone knows best,
[Ustadh] Omar Popal
Checked and Approved by Shaykh Faraz Rabbani