Sajda-e-Sahw

Forgetting how many rakaats one performed

Q:

1. I usually take the least number of rakaats when I totaly get confused in the number of rakaats of salaah and complete my salaah. I don't sit for tashahud in every rakaat in this case but I do sajda e sahw in the end after reciting tashahud by saying salaam to the right side and then two prostration of forgetfulness and again tashahud then durood and dua and then salaam to right and left. Is this the right way?

2. If not, what is the ruling on my previous salaah?

3. If it is wrong what is the right procedure?

Making sajdah-e-sahw after salaah

Q: Is it right to perform sajda-e-sahw if someone forgets to make it within salaah? When I remember, without reciting anything else, I just to sit down and recite attahiyyaat upto (abduhu warasuluh) then one salam on the right side then two sajdahs of sahw and then attahiyyaat, durood and dua and then 2 salaam. 

Forgetting to recite sunnah qiraat in salaah

Q:

1. Before starting witr, I made an intention in my mind that I will recite the surahs which are sunnah to recite in witr. Then I said softly that I make niyyah to pray 3 rakat witr, but I did not say anything about which surah I will recite. During the prayer, I forgot to recite the sunnah surahs in the first two rakahs. Then I thought that I will do sajdah sahw, but I forgot to do that too. Is my witr valid?

2. Is sajdah sahw waajib if someone intends to recite a specific surah and then forgets to recite it?