Thank you for reaching out.
With a standard
veset kavua for
yom hachodesh, a woman gets her period on the same Hebrew date each month. A
veset dilug yom hachodesh is a less common variation on that, where the Hebrew date increases or decreases by a fixed number of days each month. Because this type of
veset is complicated and relatively rare, it is often not discussed in kallah classes and many women have never heard of it.
You established such a
veset with a pattern of Hebrew dates decreasing by two days each month:
21 Adar,
19 Nissan, and
17 Iyar, all during the daytime
onah.
Your period on 15 Sivan diverged from this pattern because it came during the nighttime
onah, and if your next two periods also diverge from this pattern, the
veset kavua will lie dormant. You can learn more about observing and uprooting a
veset kavua here.
Your periods seem to be coming every 28-29 days, so it is possible that you will uproot this
veset kavua by establishing a regular
veset kavua for
haflagah, or it is possible that you will just have a
veset she'eino kavua of periods in the range of 28/29 days.
Please feel free to get back to us with any further questions.
B'Hatzlacha!
