Purposeful mistake in recitation

Salaam I have previously suffered severe OCD episodes and constantly still get waswas about Kufr. When praying Qur'an, I am constantly wary of praying incorrectly by purpose. At one point, I told myself not to pray an empty mouth letter with a full mouth, but when i got to the word, for some reason I prayed with full mouth and seem 90 percent sure that I did this on purpose. I felt regret straight away. Is this kufr, should i repeat Shahadah. Also for future reference, if someone suffers from these waswas, should they ignore every single time they think they may have committed kufr, even if they are 99 percent sure? If it turns out this thing was indeed kufr, but the person did not renew Imaan as they were not entirely certain, what is the ruling on them? JazakAllah