During this clip, at 1:24 is she saying
I went from nodding no to nodding yes...
Or does she say "nodding off"? Because I don't think you can nod no, can you?
No, I don't think you can nod "no", at least in places where "nodding" is used for agreement. In the US, nodding is used for agreement.
- To lower and raise (the head) quickly in agreement or acknowledgment.
- A forward or up-and-down movement of the head, usually expressive of drowsiness or agreement
The speaker says
I went from nodding off to nodding yes to more heroin.
Nod off means
To doze momentarily:
nodded off during the lecture.
So the joke uses a small play on words. Nodding yes suggests that she became more active or alert.
Fun fact. You shake your head in disagreement.