Answered by Shaykh Faraz Rabbani
Question: Can i make the forgetfulness prostration in every prayer, just in case I made a mistake that I didnt realize? Also, do i have to make up these prayers, since they could have been invalid?
Answer: Walaikum assalam wa rahmatullah,
It would be prohibitively disliked, sinful, and a reprehensible innovation to perform the forgetfulness prostrations for every prayer without need.
Forgetfulness prostrations are only required when one forgetfully leaves a necessary (wajib) action in prayer. It is not required nor permitted for any other action. [Shurunbulali, Nur al-Idah] The basic assumption, too, is that your actions are valid and sound until proven otherwise.
Note that there is a difference between leaving an obligatory (fard) action in prayer and leaving a necessary (wajib) action–the former invalidates prayer; the latter renders it deficient (though valid). Past prayers in which wajib actions were omitted do not have to be repeated. However, it is obligatory to make up prayers in which obligatory actions–conditions or integrals–of the prayer were omitted.
You should find out what the necessary (wajib) actions of prayer are. Any reliable manual of Hanafi fiqh–whether The Absolute Essentials or Taleemul Haq or another text–lists these.