period keeps going irregular

I had my kid in December. I decided to get mirena around February or march and I had bad side effects so I took it out a month after. My periods regulated fast the next month after that they came normally then started to come a couple of days late and little things like that. Now it's getting to the point where it'll be weeks late. I am still waiting for it. It's like 1 day late now. It's so weird and I haven't had sex in a month like before my last period so if I am pregnant then I am gonna end up on that show lol anybody else had this happen after Mirena? Or any advice