It depends on how you saved it.
If you applied the EQ via Process, this is a destructive edit. The original wav has been permanently altered.
If, on the other hand, you saved it via Bounce or Export, a new wav has been created, and the original is still safe in your project files.
For this reason, I tend to avoid the process menu, and leave all effects active in the FX bin or a bus, until I am ready to export. If you overcook something, you can always go back.
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