Leak under shower along wall and ceiling

[fango7]

Hi all,

I have a couple of leaks coming under shower tray downstairs.

One is along the wall so think might be joint between wall and tray and the other seems to be near waste tray, there is a slight hairline crack in shower tray near waste .

This happens when I leave the shower head near the shower waste plug.

My question is , is this leak along the wall a joint leak between wall and tray and the other is either the hairline crack near shower waste or could it be the actual shower waste pipe ?

I have a plumber coming next week to look , just wanted any ideas as to what potentially could be

I have attached pictures with yellow around where leak is coming from underneath and of the leak coming Down wall , which I think is the leak between the wall and tray at joint

The leak for the shower waste is on ceiling and can tell plaster is weakened due to the waste pipe or hairline crack leak.

Any ideas would be great