05 1.6 Electrical fault(s) on Sport - kam1nsk1

Wonder if anyone can help or offer any advice, I've started getting some strange electrical faults today (apologies if it is long winded but I wanted to include everything as I don't know what could be relevent).

First both my headlights failed at th same time. I wasn't sure but I thought it could be the fuses, so I swapped a couple around but they all seemed fine, so I bought replacement bulbs from Halfords.
As they are a pain to fit properly, I just disconnected the plug without taking the old bulbs out and connected the new one, just to see if this was the issue. They came on, so problem solved (I foolishly thought), intending to fit them properly tomorrow when its light.

However, 5 minutes later the central locking started playing up. When I took the key out of the ignition the central locking started making a sort of taking sound (possibly like its try to lock even though it already is). The key fob would no longer work the locks. The only thing that stops it making the ticking noise is to manually push the drivers lock down, and even this is someimes not possible as the mechanism seems to be constantly active. When I did push it down everything stops (this does not happen if you do the same thing with the passenger side), or to start the engine.

Tried repeatedly locking/unlocking manually but makes no difference.

What could this be? It couldn't be anything I did could it? I didn't touch any of the central locking/alarm fuses, all I did was swap the headlight fuse with the horn fuse to see if it was working (it was).

The central locking fuse is a screwed in affair which I didn't touch (I assume this one was for the central locking as it had a key symbol).

Any help greatly appreciated!