Sleeping bag & rucksack = This time of year, a lightweight sleepsack is probably enough.
3 x dry trainer socks - I'd only take 2
2 x bra - ok
Trek zip off trouser/shorts - ok
Hoodie - ok - is it wool? fleece?
Shopping bag reusable. - not necessary
Whistle - not necessary
Safety Pins. - yes, to hang clothes on the line to dry
Needle Thread - not necessary
Hand San. wipes. - not necessary
Money belt - yes, although this year I used one of those that hang on the belt inside your clothes and it was a heck of a lot more comfortable.
trainers - yes
t-shirts x 3 - I'd only take 2
shorts x 1 or 2 - I'd only take 1 if you're also taking zip-offs
light/torch - leave it at home
ipad? or phone? ( I may be meeting a friend or 2 on it so be nice to make contact)[/quote] - it's up to you whether you want to be connected or not. An ipad is heavy and you have to worry about it being stolen. Everybody on the camino will have a phone - for one or two calls you could borrow?
Things I did not see on your list:
Travel towel
toothbrush and paste
panties - 2
hat for sun
rain gear -
altus poncho or??
sunscreen or long sleeve gauze shirt for sun
soap and/or shampoo bar
stretchy clotheslines come in handy