How do I know when my cycle is?!

J

I had my Mirena IUD for 3 years and 10 months. I didn’t have a period for all but 6 of those months right after insertion.

My hubby & I are TTC but I only had what i thought was withdrawal bleeding, but could have been my period, for like 4-5 days after the removal of my IUD. I have NO clue what my cycle even looks like anymore?

How long will it take to get back to normal and what happens if I get pregnant before a normal cycle? I’m so confused.