how can i fix aqua w9500 slimline shower?

shower head and lead fell into bath and broke,i got a new shower head and when it was screwed together at the box i noticed a clear pipe hanging down from the box right by where you screw the lead When you go to use it the water is coming out of the clear pipe rather than travel trough and come out of the head.

Is this something i can fix by turning electric off and unscrewing the box unit,to see if it has fallen out?