I submitted the form to receive an email on Feb. 8 to amend my 2020 return because I got my stimulus after filing, but I didn't receive the email yet (it's almost 7PM)

Not everyone will be able to access the return to make the change ... those who are will be contacted.  Those who cannot will have to wait until the IRS processes the return and makes the correction needed. Make sure to check your spam folder. 

Same here I am also waiting for the email.

Mike

So have the emails gone out or not?

So when the IRS gets it, they'll just see that it was submitted before the stimulus was actually sent to me, and change it on their end?  I just don't want to get slapped by an investigation or fees or something is all.

Due to the late mailing of the stimulus payments there are going to be millions of returns with  this "math error" that the IRS will automatically correct ... you will not be drawn and quartered.