Mini pill and period question

It's my first time on any type of birth control. I had my daughter five and a half months ago. Does the mini pill make you periods irregular. My last period was last month for five days I don't think they have become regular as that was my second period that was actually a period. I know pregnancy is a possibility but I'm wanting some input before I just go buy a test and not needed. Idk when my period should come. Thank you