What's going on here? מַה זֶה?

If you look at the first word of the parashah in a סֵפֶר תּוֹרָה (sefer Torah, Torah scroll), you’ll notice that the word “וַיִּקְרָא‎ (vayikra, and God called)” is written with a small aleph. What’s the meaning of this small aleph?
The Ba’al Ha-Turim gives a backstory. Moshe wanted to write the word “וַיִּקָר (vayikar),” since that’s the word that describes God speaking to people with less thought, almost as if it were a מִקְרֶה (mikreh, accident). Moshe wanted to write it this way because he was humble, and he didn’t want people to think he was so great that God spoke to him with so much thought and meaning.
God insisted that Moshe write the full word, “vayikra.” Still, Moshe wanted to downplay his own importance, so he wrote it with a small aleph, to make it look more like the word vayikar.