Assuming i survived, i'd head straight to swithland woods quarry.There's a dive center built into the solid slate and its a deep old quarry in the middle of a dense forest. The stone should keep me pretty shielded, and hopefully the water will be covered enough by the forest canopy (provided it isnt on fire) to keep it just safe enough to not kill me straight away.
If the actual local area was hit then i'd be dead from radioactive beans pretty soon, but if Leicester wasn't directly hit but reasonably damaged, i'd stick to the country side for foraging and hunting.
(or realistically, die horribly)
(or shoot myself with a bow because i can't face a world without tea)