Joystick settings

I'm brand new to X-Plane, thanks to Justflight's half price offer, so maybe doing something wrong.

I spent some time setting up my joystick, pedals & throttle before trying my first flight and all seemed to be OK except that the 172 throttle was reversed, i.e. it was at full throttle when my hardware throttle was at idle, despite me having set the throttle correctly. When I reloaded the 172 the throttle worked correctly.

Now I have just 'loaded' the Bell helicopter and it immediately took off and flew around uncontrollably and when I checked its throttle was at full power despite my throttle being at idle.

So do I have to set my controls for each aircraft or is something odd going on?

Thanks for any help.

Dave