A word about stretching first-- the point of a stretch is not to push yourself to the point of pain. Discomfort is okay; that means you're having an effect. But discomfort is the only edge you should ride, not pain. Duration, not intensity, is the key here. Hold each stretch for a minimum of 30 seconds, upwards of a full minute if you feel you'd benefit from it. Do the stretches that target your problem areas at least three times a week, preferably every day. If it's persistent wrist pain, do the wrist stretch multiple times each day. Set an alarm on your phone if you have to.
For major rehab, apply heat or ice thoroughly for 20 minutes before beginning. I recommend heat on the neck and ice on the wrist muscles, which actually live up near your elbow (we'll get to that later).
If you keep this up for a couple weeks, you'll probably agree with me that it was worth it. And remember: breathe.
There's two variations to this, shown above, and you should do them both. Sit on a chair and use one hand to grip the bottom of the chair. Use your other hand to pull your head in the opposite direction of the hand gripping the chair, straight to the side (laterally towards your shoulder). Counteract this motion by keeping tension with the hand gripping the chair. Hold.
Variant two is similar, but you pull your head forward and at a 45 degree angle. Your gaze should rest at the inside of your opposite knee. Hold.
Ah, pecs. Otherwise known as pectolaris major and pectoralis minor when they're not at home. Pecs are drastically underexamined in shoulder problems (most of the time) which is a tragedy because they're hugely influential. Your pecs are what cause your shoulders rounding: they function to draw your arms forward and inward, towards your chest, which not coincidentally causes your shoulders to do the same if they're too tight.
Don't underestimate the importance of pec stretches. Seriously. If I could have every office worker do only one stretch religiously, it would be this one.
Stand in a doorway, toes lined up with the threshold, stretch your arms out to either side so your elbows rest on the frame, and lean in. This is deceptively simple, so make sure you lean in with a bit of caution-- your pecs might be screamingly tight. Try this again multiple times with your arms in different positions until you find the one that gives you the most resistance. Different arm positions will target different parts of the muscle. Your pecs fan out from the head of your humerus to all along the clavicle and sternum.
If you, for whatever reason, dislike this stretch, don't have a suitable doorway, or just want to target one side over the other, use the following variant:
Face a wall with your whole body. Stretch out one arm at shoulder height out to the side. Draw your gaze over the opposite shoulder, turning your head primarily and not your torso.
Levator Stretch, aka Ws
This stretch has the potential to be much harder than it looks. If it's difficult for you, go to the extent you're able each day, and you should gradually increase your range of motion.
Begin by standing flat up against a wall. You'll find your back arching and trying to curve away, essentially to get out of the stretch-- don't let it. Be mindful of posture while doing this. Your arms start up over your head, and then are gradually lowered, elbows first, toward your waist. Do this slowly. When you finally get to the lower limit of your range of motion, hold there.
This targets the levator scapula, a muscle that travels from the inner angle of your shoulder blade to the base of your skull. It's a common culprit in tension headaches.
Unless you have actual carpal tunnel, which is a nerve problem, what presents as wrist pain is actually an issue with the muscle bellies of the wrist flexors and extensors. These muscles don't live in the wrist, but up near the elbow and along the main breadth of your forearm. What runs over the wrist itself is the tendons, and stretching or performing massage on them all the live long day will not cause them to release, because they're connective tissue.
Accordingly, if you have wrist pain, you must stretch the forearm. This is more difficult than it seems, because simply pressing on the hand to perform what would seem like an effective stretch frequently does nothing, and at worst, compresses the joint and compounds the problem further. To make up for that, we will do a pin and stretch technique, wherein you use your thumb to pin part of the muscle in place before performing the stretch. This forces the muscle to take the stretch, instead of allowing the tendon to, uselessly, take on that burden.
This will require quite a bit of pressure on the part of the opposite thumb. Don't be afraid! The likelihood of you damaging yourself is quite small. If you're strong enough in your opposite hand to apply a lot of force, chances are your other hand needs that much force for this to be effective. Always, though, listen to your body's signals and be smart about what you inflict on yourself.
Icing first before this is always a good idea.
Begin with the hand flexed upwards and back toward the elbow. Take your opposite hand and use your thumb to pin, hard, somewhere along the main muscle bellies. The placement of my hand in this picture is a good starting location-- on the outer edge toward the elbow. In general, you'll want to move up and down along that line from elbow to wrist, at the outside, and do this stretch multiple times. You can also perform it pinning the other main muscle here, which runs more centrally from elbow to wrist.
Then, while maintaining the pin, flex your hand all the way down in the opposite direction. Repeat.