I want to repeat the due cards first, but unfortunately Anki wants me to go through the learn cards instead and shows me the due cards after I finish or skip the red cards / cards to learn.
In the settings I chose show new cards after due cards (Reihenfolge Neu/Wiederholung → Nach Wiederholung anzeigen)
Anki treats small steps and steps that cross a day boundary differently. With small steps, the cards are shown as soon as the delay has passed, in preference to other waiting cards like reviews. This is done so that you can answer the card as closely to your requested delay as possible. In contrast, if the interval crosses a day boundary, it is automatically converted to days.