Finally got power into the shed, the "pal" really let me down and didn't do anything other than drop me off some armoured cable he got from work and I never seen him again! Anyway, installed the cable to the DB in the house (not wired, just ready to be wired) and ran it out and to the shed, all done properly along the wall and under ground then along a fence, all 22 metres
Got a local Electrician to come round and wire it all correctly and sign it off etc... Lovely having power and light!
Word to the wise, don't buy those sockets with USB built in. I thought they'd be a good idea for charging various stuff whilst in the shed but no, one of them sounds like a hive of bees it buzzes so much and stops when you plug something in! Doing a bit of reading online would suggest they're none too popular. I didn't get them from ebay etc I got them from Screwfix so thought they'd be fine and never give it a second thought. The MCB in the shed is currently off for the sockets as it was that bad I didn't want to leave it on overnight. £13.50 for 3 replacement sockets (without USB) so I'll be replacing the fronts asap so not too bad really.