weird and worrying behaviour from my herman tortoise???PLEASE HELP!

[connorfitzy]

I am very worried about my herman tortoise, at the start of this sumemr he made the transition from living in a vivarium to living outside, I was away for a while when he first made the transition, but after recently returning, I have seem very little of him, as he is just hiding away in his shelter all day, I am worried because not only is he not gaining energy from the sun, but he is not drinking or eating, I am very worried, I don't know what to do? has anyone had similar experiences?