Postpartum periods. When did you get yours and is it regular?

I got mine at 6 weeks pp and had another one 2 weeks after my first. Since then my periods have been regular and started at the same time every month. Now that I’m 6 months pp I haven’t had my period this month. I’ve had 5 periods since I’ve given birth and my son is 6 months. Has this happened to anybody else? Is this normal?

Yes my husband and I have had unprotected sex and I’m not on birth control ( I have other thoughts about that) im not weighing out the option of not being pregnant but I’m almost sure I’m not. Just curious if having regular periods and then irregular is normal after having a baby