Doubts in Salaah

Q: One on numerous occasions doubts the number of rakaats one had read in salaat. Does the salaat have to be repeated?

Q: Today at zuhr I had experienced a lot of doubts in the prayer and here is the list:

1. Weak doubt happened after sujood about back being straight in 1st rak'ah.

2. Whether accidentally extending the meem in Sami Allaahu liman hamidah, unsure.

3. In my 3rd rak'ah I stood straight up from sujood, and then doubted whether I made two sujood or not, as I was already standing I didn't go back and I could only be firm in that I definitely made 1 sujood but doubtful about 2nd and as 2 sujood is one of the essentials for a valid rak'ah I made full Tashahhud in my 4th rak'ah and stood up to let that 4th rak'ah take the place of the third in which I doubted the two sujood.

4. In the replacement rak'ah I doubted saying Rabbi instead of Rabbil Aalameen, but it's a very weak doubt.

5. During the sujood I then rose and again doubted whether I did 1 or 2 sujood, I think after beginning Tashahhud or maybe before. It seems like a pressure doubt, as. I don't want my salaah to be invalid. Anyway I recall having Rabbighfirlee in my mind and this just leads me to thinking its probably a doubt, "but what if its not?" 

Then during this with my wandering thoughts, after the Shahadah I said something starting with ashhadu and ending in Qadeer, but before that I already said the Shahadah so I repeated it mistakenly, even though I said something different.

Then said salaams and did two sujood out of forgetfulness and even in here I  doubted about saying the full durood.

What should I do? I have regular doubts affecting me in prayer and Wudoo'. Do I repeat the prayer?

Q:

1. I went to sujood. My finger was on something, so before reciting anything I flicked it away and put palm flat and carried on.
2. In third rak'ah I rose from sujood and like in the position where you support yourself to get up I moved my left foot flat and realised its not sitting before getting into it and moved my foot back upwards and supported myself up like about 10 seconds from sujood takbir to the basmalah of 4 rak'ah.
3. Disc solid small spot, not paint, perhaps likely a eye secretion under my eyelid at about 6:30, I made Wudoo' at about 5 to 4 (3:55) and was done with Fajr at perhaps 5:15. (I was awake for Dhuhr all way to &past fajr), should I disregard it as having come later and ignore it?

Q: A person doubts whether he is in the 3th or 4th rakaat, and in his mind he has no clue which one it would be. Thus he takes the lesser amount. Should he still sit after the 3rd rakaat and make tashahhud, as there is a possibility that it is the 4th rakaat?

Q: When I pray salah I don't remember how many sajda I do if I did 1 or 2 sajda.  If I can't remember how many sajdas what shall I do?

Q: I have short term memory problem when I am praying salah. Sometimes I don't know how many rakat (rakah) I did, what shall I do then? I always don't know how many sajdah I did. If I did 1 or 2 sajdahs I don't remember. If I do more than 2 sajdah or do less than 2 sajdah would my salah be valid? I don't know if the cause of my problem is shaytaan. If I don't know how many rakaats and sajdah I did, what can I do? If I don't know, can I just do 1 more rakat or 1 more sajdah?​

Q: I forgot a lot in namaz. When doing sajdah sahu I even forget I have offered the salam and so I used to repeat my sajdah sahu. But now I offer salam to both sides and then do the sajda sahu knowingly. Is my namaaz valid?

Q: If one has a habit of forgetting multiple things in a Salah such as number of rakat, number of sajda, first tushud and so forth, how that person would perform his salah?

Q: If a person does get often in salaah the doubt as soon as he raises his head from the sajdah, whether its from the 1st or 2nd sajdah, what should he do? Should he ignore the doubt and complete the salaah and consider it complete?

Q: If one has frequently doubts in salaah, that he is recording his salaah with his audio-record function of his phone to check afterwards whether he prayed correctly if some doubt arise about something. Now say he is praying Zuhr and in the last rakaat when he sits after the sajdah, he does not not know whether this was from the 1st sajdah or 2nd sajdah i.e. he cannot totally remember that he did another sajdah before it, but continues on this basis (because he can check with the audio-record anyway) and finishes his prayer. Now afterwards when he checks his audio-record it shows that he did 2 sajdahs thus prayed correctly. Is the salaah valid ?