It sounds like with your knee you may have a medial meniscus tear. The knee has 2 shock absorbing c-shaped pieces of cartilage in them that lies between your thigh bone (femur) and your lower leg bones (fibula & tibia) the one on the inside of your knee is called the medial meniscus and the one on the outside of your knee is called the lateral meniscus. These tear easily and are more susicitable to being retorn if you have had one before. Symptoms are pain and tenderness on the inside of the knee, giving way or instability in the knee, locking/catching, increased pain with twisting motions or squatting. Treatment consists of anti-inflammatory medications and usually surgery (arthroscopic) to either repair or clean up the knee and physical therapy following surgery to help rebuild the muscles and get your full range of motion back. Bracing is also sometimes used. If you want to try a brace you need to look for a neoprene brace that has hinges on the side. Here is a link so you can look at the type I'm talking about. http://www.supportsusa.com/knee/hinged/drytex-hinged.htm
You may also have sprained or torn a ligament in the knee but usually with this you have a lot of instability and giving way, swelling and bruising. I believe it is probably a meniscus tear, but want you to know there is a chance of a ligament injury as well.
You need to see an orthopedic doctor that specializes in the knee and have a MRI done. This will show any abnormalities of the cartilage, ligaments or tendons.
As far as your shoulder, this sounds more like a neck injury. You may have a bulging or herniated disc that is pressing on a nerve. Symptoms of a pinched nerve in your neck include numbness,tingling, weakness into the arm. A lot of times this can resolve on its own or with conservative treatment such as anti-inflammatory medications and exercises. Sometimes physical therapy is needed and epidural steroid injections into the neck. In severe cases surgery is needed but this should be done once all conservative treatment has failed. You can treat this on your own for a couple of weeks and see if your symptoms start to improve. If not, then you should see either an orthopedic who specializes in the cervical spine or a neurosurgeon. Once again, a MRI will be done to look at the structures and make a definite diagnosis.
Things you can do at home for both problems are take 400mg of ibuprofen three times a day with food. Exercises, I will attach a link for exercises for your knee and neck. You can use ice packs on both, 20 minutes at a time three times a day. Rest the knee, no impact exercises (running/jumping) you can swim. If a certain exercises increases your pain, then do not do that one.
I wish you good luck and hope you get to feeling better soon. If you have any further questions, please let me know and I will get back with you as soon as I can. I will not be back on tonight due to my husbands grandmother passing away and we have to be at the funeral home, but I will be back on tomorrow morning before the funeral. Hope you have a good day and thanks again for using Just Answer.