When to amend return

I filed my return nearly two weeks ago and realized today I did not include Form 8889 (Health Savings Account). It doesn't affect my tax lability, but I understand from a previous thread that I need to amend my return.   The question is when.   

 

I got a message from TurboTax that my return was accepted within hours of filing.  My tax owed left my checking account the next day. I assume I can amend now, right?

 

Also, I will lodge a complaint.   Form 8889 was included in my 2022 return and I'm surprised that TurboTax did not by default include it in my 2023 return.  I think it should have.