Looking on the internet deeply has found these results:

I did what I supposed to do is the most popular phrase on the web.

I did what I should do 1355,000 results on the web	I did what I supposed to do 11,060,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
If I did, what should I do with it?	Second, even if I did, what was I supposed to do? Because this is the first time I'm feeling like this, I didn't know what I was supposed to do. From the day this started, I didn't know what I was supposed to do, Who I was supposed to stand by. You know, I did what I'm supposed to do. I'm an American, I didn't know what I was supposed to do. Okay, look, here's the deal all right? I came back and I did what I was supposed to do. They did what they were supposed to, and I did what I was supposed to. I did what I was Supposed to do.

I did what I should do

1355,000 results on the web

I did what I supposed to do

11,060,000 results on the web

More popular!

Second, even if I did, what was I supposed to do?
Because this is the first time I'm feeling like this, I didn't know what I was supposed to do.
From the day this started, I didn't know what I was supposed to do, Who I was supposed to stand by.
You know, I did what I'm supposed to do.
I'm an American, I didn't know what I was supposed to do.
Okay, look, here's the deal all right? I came back and I did what I was supposed to do.
They did what they were supposed to, and I did what I was supposed to.
I did what I was Supposed to do.