Unless you are using a spot meter, the camera must be very close so it only sees the darkest area. If your dark area is too small the camera viewfinder includes some lighter areas. You will get a false reading. Create a larger dark area temporarily to get a meter reading. View it very carefully to be sure it matches the small dark area.
Some photographers use a spot meter to include ONLY the area being metered.
Set camera two stops darker than this reading and take the picture. At this setting the film still has enough latitude to include good shadow detail. Meter the lightest part of the scene in which you wish to show textual detail. This reading will be needed in order to know how long to develop the film. This indicates the contrast range in your scene.