Little guesswork here - if thats a brushed motor, yes, it makes a diff and direction can't be reversed by switching wires. All the brushed motors I've had have been labeled (+) and (-). I assume you've made sure its connected correctly?

There should be a throttle channel reversing switch on the radio - find it and set it the other way and all should be good. There is another reversing switch for the strg as well if thats not correct. Sometimes these switches in the radio are labeled as channel 1, 2 - channel 2 is the throttle.