Postmenopausal bleeding (no uterus, no ovaries)

If it were me, I would make an appt with my gyno. Let her know what is happening and you need to discover what is going on in your body.

Gravity is more than correct.

The probable causes are from a lack of hormones in the vaginal area, but you won't know without that check up.

Google summary of the standard causes/practices:
"Postmenopausal bleeding without a uterus (post-hysterectomy) is uncommon and requires prompt medical evaluation to identify the source. Potential causes include vaginal atrophy (thinning tissue), vaginal or cervical polyps, granulation tissue at the vaginal cuff, or, rarely, malignancies like vaginal or cervical cancer.
Common Causes After Hysterectomy
Vaginal Atrophy: The most common cause, where low estrogen causes vaginal tissues to become thin, dry, and fragile, leading to bleeding.
Granulation Tissue: Improper healing at the vaginal cuff (where the uterus was removed) can cause bleeding.
Polyps: Benign growths on the cervix or in the vagina.
Infection: Infections or inflammation of the vaginal area.
Medications: Use of blood thinners or hormone therapy.
Vaginal or Cervical Cancer: While less common than uterine cancer, malignancy in the vaginal vault or remaining cervix can cause bleeding. "