Flow is pleasant and often productive. It may also require some guardrails to be healthy for AuDHDers, especially those of us on the very monotropic side.
It's often easy for us to get into flow and hyperfocus, and to stay in them until they stop feeling pleasant.
Adding in more rest and recovery, including preparatory rest as needed, can really help!
It's also okay to avoid flow states for a period of time, as I am right now for the most part.