Higher magic and all its fun

[SnowDream]

Hello:

I am having a little trouble understanding higher magic lv 2. When Amelie has that skill, and she heads into combat, the book icon fist read 4/4 spells. I use one trap spell (1st level, 5 MP) and suddenly it says 1/4 spells. So... am I doing something wrong or is the 4 casting/turn just a typo? Would it be the same for higher magic lv 3?

Thanks.