Letrozole and progesterone

Joey

Hey guys, so I have pcos and had been on a mix of letrozole and progesterone / clomid and progesterone from September 2019 until February 2019. Did not take any medicine in March and had a normal period on time. April’s period was 5 days late and I haven’t had a period since April. Is this a normal occasion when abruptly stopping those medications? I’ve taken quite a few pregnancy tests along the way and all of them have been negative