'64 dart amp gage

The way I see it for now:

Seems like the alternator is trying to "put out"

But maybe not enough OR the battery is just way down.

Is there any chance you have REVERSED the ammeter leads? To find out, shut everything OFF make certain the ammeter is centered, and turn on the headlights. Should move to the left, discharge.

If this happens, the alternator may be toast.