As a neurosurgeon who mainly treats musculoskeletal conditions, I would first recommend considering whether your wrist pain could be related to any minor injuries or repetitive overuse from activities other than using the mouse.
If there is no such history, then mouse use itself could certainly be a contributing factor. The key issue is that when you hold a mouse, your wrist is often kept in a constant state of extension. Over time, this continuous extension can overload the extensor tendons and potentially lead to tendinopathy.
One practical approach is to place a supportive wrist pad under your hand so that your wrist stays in a slightly flexed position. Even a small degree of flexion allows the extensor tendons to relax, reducing unnecessary strain. Another good option to consider is switching to a vertical mouse, which can help minimize wrist extension during use.
I hope this explanation helps you better understand the mechanics behind your symptoms and gives you some practical strategies to try. Wishing you relief and a smooth recovery.