Self cast not working as intended (probably)

Pretty simple to understand bug, whenever I use quick + self cast with, say Morgana's or Janna's E and have my mouse over an ally champion, Morg or Janna will cast it on that ally instead of me, which has quite literally gotten me killed just because I happened to have my mouse over an ally. If this is what was intended, please add an option to make it so I can have myself or an ally as my preference when conflicts like that arise.