Earthworm Jim: Special Edition, per its game page, is "notable for being the very first game to use the DirectX API."
DirectX is not the same as Direct3D. The latter is a subset of the former, but is only included in DirectX 2.0 and newer.
Timeline:
- September 30, 1995 - DirectX 1.0 is released.
- November 30, 1995 - Earthworm Jim: Special Edition is released.
- June 2, 1996 - The first version of Direct3D is shipped with the release of DirectX 2.0.
Earthwork Jim is also seemingly a 2D game, so there's at a glance no reason for it to use a, at the time unreleased, API meant for rendering 3D scenes.
So basically, while DirectX 1.0 games might exist, that alone does not make them use Direct3D.