Hi Bexie and welcome to the forum.
When I heard last August that I was to go onto Byetta injections, I was petrified - but only because injecting was unknown territory for me. Looking back now, I can see that there really was nothing to be worried about. The injections are painless and dead easy once you have got the hang of it. Just follow the DN's advice on how to inject, and the manufacturer's instructions on where to inject, and you will be fine. As well as the Byetta pen you will need a prescription for needles. The Byetta people recommend using 8mm needles but make sure these are 31gauge (the finest gauge). I find the BD Microfine needles are very good and nearly all chemists have them in stock.
As regards storing the pens, until first use they must be kept refrigerated, but once in use they must be kept at a temperature below 25ºC at all times. You are supposed to inject twice a day, before breakfast and before your evening meal, so not sure why you would want to take the pen to work with you. But if you need to travel with it and are not sure whether you can keep it below 25ºC, then I would recommend using a Frio bag to store it in. This link to the Frio website will tell you all about the bags. They are not expensive, they do mail order and usually arrive by return post.
http://www.friouk.com/
Keeping the pen in a fridge is fine and whenever I am on holiday in a hot country I try to ensure that the hotel can provide a small drinks chiller in the room. If not then the Frio bag gets used. I have even used a room safe because these are usually tucked away in a wardrobe and thick lined so they stay quite cool whatever the outside temperature. Whatever you do don't carry it in a coolbag with an ice pack because this can freeze the liquid and freezing makes the medicine useless.
If you are travelling on a plane
ALWAYS take the pen & needles in your hand luggage, never pack then in a suitcase. You will also need a letter from your GP addressed "To Whom it May Concern" stating that you are diabetic and must be allowed to carry your medication in your hand luggage. Some GPs charge for producing a letter, but its better than being refused permission to board, as I have seen happen to some people. As long as the airport security people don't insist on keeping the letter, you can use it over again for flights.
I'm sure that once you get started on byetta you will have a whole host of questions. There's a growing number of us on the forum who use it so there will usually be someone around who can provide an answer. Just one point though about its use - and I hope this isn't going to put you off. Your diabetes team MUST start you on the 5mg pen, not the 10mg.
This is absolutely essential. The regime is a MINIMUM of 30 days at the 5mg dose before you move up to the 10mg dose. This stuff is extremely powerful and is alien to the human body so not something that your body will be used to handling. Feeling nauseous is a common side effect until the body becomes acclimatised to the medication. Some people don't suffer from it at all, or it can last just a few days, but in some cases it can last a month or more. Your support team must not up you to the 10mg dose until you are completely clear of any feelings of nausea. If you start off on 10mg or are moved up to it too early then you will become extremely sick and will be unable to hold in any food. Unfortunately too many doctors think they know better than the manufacturers and completely ignore the practitioner guidelines - but its not the doctors that suffer the consequences, its us.
As I said, I hope this last bit hasn't put you off. I would rather you had a clear idea of the side effects in advance (and nausea is the only one) than find out the hard way and worry what's gone wrong.
Good luck and please let us know how you get on.