As salamu aleykum,
If one concludes his salaat with the taslim, but he doubts that he has done 1sajdah to less in the last rakaat, what does he need to do?
Should he made 1 sajdah after the taslim en dan make tashahhud and taslim again, then make 2 sajdahs of sahw and then tashahhud and taslim again ?
Thus in the last rakaat he would make 5 sajdahs, 3 tashahhuds and 3 taslims, is this correct ?
Also tt happens on a regular basis that i am doubting that i have forgot one of the two sajdah's when praying (before making taslim)
What should i do in this case ? Will sajdah sahw suffice to remove my doubt ?
Was salaam

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.

If the praying person doubts whether he has offered one or two prostrations (in the prayer), there is difference of opinion among scholars as to what he should do. Some of them said that his doubt does not count, nor anything is due on him, for doubt after finishing the act of worship is of no significance. Others hold the opinion that it has to be taken into consideration. But the former opinion is more preponderant in our view. Hence, nothing is due on that praying person. That is even more confirmed with regards to the person who often has doubts.

The view that we adopt and the most preponderant opinion is that whoever doubts so much that the matter has become to him like obsessive whispering, his doubt should not be taken into consideration, but he should prostrate after each prayer in which he has such doubt to be in defiance of the Satan. For further benefit, see Fataawa 83932 and 86560.

Allaah Knows best.