This is really bad advice. You should stop reading this text as soon as you see he's had the problem for a week. Obviously chronic injuries are a handicap, and you don't reverse a handicap by delaying it with a few tweaks like a new mouse or a new keyboard. You have to actively rehab yourself into a stronger version of yourself, what you were before when you were young. You can even become better. Do you want to be the guy who can only "kinda" work at a computer if he has his proper setup or do you want to be the guy who comes in, lays his thick forearms on the table and start typing without a care in the world. I know what I want to be.

My advice for treatment : First, start by fixing potential neck, scalene issues. There are a lot of nerves there and you can waste many years working other muscles along the way and it will never solve the problem if it comes from the neck. You also need to check the chest area to see if it causes a problem. After the neck there's the shoulder. The rotator cuff muscles can become very weak and also cause nerve impingment. So check your shoulder area. Especially the muscle called Infraspinatus. Then there's the upper arm. Usually for computer geeks it's unlikely to cause problems. But if you have elbow pain I would really check the triceps for issues. Then you have the forearms. I would say that the most important muscle you can strengthen is the muscle that helps extend the fingers. Extensor digitorum might be the name, I'm not sure. This muscle takes a lot of abuse when using a mouse and a keyboard and for the people that get the problems, it only becomes weaker with time. A strange kind of weak because it will always work, but it will work in a non-optimal way, so you will feel refered pain at the wrist or hand area. This muscle can be worked in a number of ways. Extension bands (brocoli bands), you can plunge a closed hand in a bag of rice then open the hand against resistance. You can also work with dynamic tension by opening your fingers against your other hand, with resistance. There are also isometric movements like wall fingertip pushups. And there's also the usual dumbbell eccentric/negative movement you can do. Most people use this with great success. If you want really strong/big forearms and hands, you can practice your grip too. There's a subreddit for griptraining that you can check out. I could write a lot more about it but I don't know if people will read or find this. When people get this problem, a lot of them become so incapacitated that it becomes harder for them to seek help. They will go to a chiropractor or PT first and they WILL waste their time and money. The way you treat a chronic injury is by doing chronic good things. The way appointments work (once or twice a week) can never work. It can remove some pain but never heal you. This is why gym people manage to heal themselves, without really doing the perfect program and normal people get stuck with depression and pain.

Recommended : http://www.triggerpoints.net/