Doubts in Salaah

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?