iOS 13 introduced a new love/hate feature: Memoji stickers. Now, whenever you open the emoji keyboard on your iPhone or iPad, these stickers take up the leftmost space. That alone would be fine. However, the stickers also replace the panel showing your recently used emoji (or at least shifted that panel right).
If you don’t like the current state of affairs, don’t fret. You can quickly remove those pesky Memoji stickers from your keyboard.