Think I might have come across a reason for the twitching/cramping/etc.
Went to the GP to have a check up, got a call from the doctor as I was leaving and apparently the blood tests I had done months ago weren't looked at properly.
Turns out I'm borderline vitamin D deficient which might explain aches, sensitivity and twitching.
Not sure how it's possible as I eat meat, including liver - drink lots of milk and walk to uni everyday so diet wise it's not very likely that I should be insufficient.
Very weird...so going to start taking supplements and see if that helps at all.
Not convinced as my mum made me take vitamins all the time when I was little and I've kept up the tradition.
Who knows!? Mybody seems to be full of surprises