My 3yo Hermann tortoise used to be really active and was always up and about, annoying my cat and wanting out of his viv. Lately he just hides and only comes out to eat. I still bring him out every day and bathe him every other day. I haven't changed the type of food or salad i give him. The only change that has happened is i was on holiday for 3 days and had to take him to my parents. He had everything with him including his viv. Has this maybe frightened him? I'm quite worried, although he's still eating.

I suggest that you click "The Tortoise ...." box. Have a thorough read through the topics & print off a free Care sheet. 

Vivs are not suitable for torts.. 

It should be outside in Summer in a wood sided pen with wire mesh above [depending on it's size] & a house so that it feels secure. It will need a 15sqm enclosure in a few years time.

It can be hibernated for 3mths this winter & 5mths when it's 5yrs. That's subject to a satisfactory weight chart.

You say it's feeding so that's a good sign. I appreciate that the situation is not your fault - the Pet Trade love selling vivs to tort' buyers, PROFIT is their only interest.

Now you can give it a good quality life at last.