User blog:InvaderrrZIM/Double Space after Period?

So ermmm, whenever I double space after a period, this weird ? pops up... ? Like this, I didn't type that second question mark back there.

Before it used to autocorrect and reduce it to one space lol. Did I mess something up on my computer or is this a wikia thingy?

Also, this got me thinking...how many spaces do YOU put after a period? I was taught to put two, but my roommate told me that it's supposed to be one, and I seem to be one of the only ones affected by this ? thing...