heres alittle help :]
to make the character flip when u press a key add this code into the left and right
key brackets:
_xscale = -50;
replace the number with any number and change the - to a + if its the wrong way.
(i had -50 for my game because my character is small, u may wanna make the -50 a -100, its the width of ur char thats flipped)