Does my mouse have a tumor or is it something else?

My mouse has something that looks like a tumor by her leg. It is pretty big. I turned her over and it was purple on the bottom and it was soft when I touched it. She can’t run on her wheel or fit through her tube. She also limps when she walks. She also has something that looks like a cut near it.

Does that sound like a tumor? What could I do to help her?
Thanks.
I think she is 2 years old. I’ll take her to the vet.

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