There are lots of possible reasons for achy joints, including injury and long-term conditions such as osteoarthritis. You would really need to see a doctor or physiotherapist in order to determine what kind of issue it is that's causing your pain. They can do an examination and may then be able to offer treatment/exercises to help.
In the meantime, you may find it helpful to look at my pages on joint pain:
Do you have questions? Please feel free to ask.
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