Can we get a breakdown of what each word means here? :D
Is 'Dwi'n wedi blino' acceptable in this context?
No, yn and wedi cannot be used together like that.
yn marks a continuing or uncompleted action, and wedi marks a completed action. An action cannot be both at once:
I don't understand. If "wedi" is used for a completed action, why is it used for "I am tired" which is not a completed action?
That is a completed action in Welsh.
'I am tiring/getting tired' (dw i'n blino), and then 'I am tired' (dw i wedi blino).
Thank you. This was very helpful
Could we say "Dw i blino" and leave out the "Wedi"?
Or isn't that allowed?
No, that would not work. See the course notes for explanations and examples of this pattern with wedi.
There are several ways to find them - go to https://forum.duolingo.com/topic/924/hot and then look for the sticky discussion 'Course tips and notes'.