PC got sicky

My personal laptop gets uppity all of a sudden. The graphics went haywired. The header, menus and everything else basically became black and striking in contrast. I was very sure I didn't turn on the accessibility function. The scrollbars also went missing. I boot it up again and to my horror, the Microsoft Office suite went bonkers. Icons and shortcuts went missing and they somehow became not available. I then reinstall Office but it turns out the installation didn't manage to complete itself. Anyhow, the office programs work again but now, fonts are missing. I download the fonts and redeploy them.

It seems fine again now, but Excel still can't open one excel sheet that contains macros regardless whether I enable or disable it. Rats. It feels like my pc now has got this disability, as if a finger is not working.

Now. How on earth do you explain something like this. I'm from an IT background but can't muster any acceptable reasoning for it. I can only blame it on it's old age. 4 years old.