This is the other half of the gravity test. Pain that worsens upright could still be several things — but pain that also reliably eases when you lie down or put your legs up completes a very specific picture: something is pooling under gravity and draining when you remove it. That something is usually blood in veins that can't empty properly.
Many women in our community describe the same evening ritual without knowing its diagnostic value: getting horizontal and feeling the heaviness slowly drain away. Mentioned at an appointment, that one detail separates venous pain from the conditions it gets mistaken for — endometriosis and period pain don't usually care about posture, and joint or spine pain follows movement rather than the clock.
If you answered yes, your pain has the venous signature's second component — see what PeVD actually feels like. If lying down doesn't help, that genuinely matters too: it weakens the venous hypothesis and steers attention to the other candidates.