My point is what exactly should a person do in the moment he/she realize that he/she missed or added a part of rak'a to his prayer.
Here two exemplary situations:
- I stood up after finishing the 4th rak'a (and maybe missed the tashahud) and while reciting Quran realized that I'm in my 5th rak'a should I immediately sit and do the tashahud and the sujud a-sahw or complete the rak'a I began?
- I missed the 2nd of the two sajdas and stood up and realized I have missed the sitting between the sajdas and the 2nd sajda should I immediately transfer to the sitting between the sajdas and complete from this point, or complete my prayer from the "position" I was at actually?
I'm looking for a practical answer: What is more correct going back to the point where the mistake has been done or continuing and performing sujud a-sahw?