Can't shutdown MacBook Pro after upgrading to macOS High Sierra

Hi, I have a late 2013 MacBook Pro, i7, 16gb ram, 1tb SSD.

I recently upgraded to High Sierra, 10.13.3

I initially noticed that mail was no longer able to search properly - it fails to find e-mails that I can see are there and now the 'flagged' folder is empty despite me having just flagged 4 e-mails.

Then I noticed that spotlight can no longer find applications.

And finally, when I attempted to installed the latest High Sierra update, I realised that I can no longer restart - which I need to do to install. To shutdown I have to press the power key until I eventually power off.

Two days ago an application - Final Cut Pro X began to crash repeatedly when I attempted to copy something.

I have powered on whilst pressing cmd, option, p and r.

I have powered on whilst pressing ctrl, shift and option.

Can anybody help?