Xperia Z5 :: Home Screen Not Responding

I've recently got my Z5 (upgrade from Z3) literally on Monday 23rd Nov.

I've loaded most of the stuff I had on my Z3 and not loaded anything else that I didn't have on the Z3 (eg. Apps).

However, the first morning upon trying to sleepily swipe the alarm off, it wouldn't work so when I eventually opened my sleep encrusted eyes to see what was up it had a little pop up message saying "home screen not responding: close | wait" so what I pressed as I was trying to get it to stop blaring out Queen at the ungodly hour.

Didn't think much of it but over the past few days it's been doing it still. This morning it did the same thing but it also does it during the day too when I take it out and unlock to start using it.

I'm not sure if it's a temporary thing and whether it's because it's the first usage and it's unhappy with my choice of alarm music, the music I listen to during the day via Bluetooth headphones or maybe the somewhat RAM hogging weather live app I have running as a live background function.

I tried Google but it came up about home being touch unresponsive which this isn't technically doing. If I press "wait" it's a bit like a pc in that it will sit frozen for a minute then start working.