Right now, no, there's no way to specifically check for it. The easiest way to set it up so you CAN check is to have a private variable that controls whether or not the sprite is mirrored, like so:
On Right Arrow pressed
-- Set Direction to 1
On Left Arrow pressed
-- Set Direction to -1
If Direction = 1
-- Set sprite to Not Mirrored
If Direction = -1
-- Set sprite to Mirrored
Having a variable like that has plenty of nifty uses depending on what type of game you're making.