Figuring out my cycle

Hi all!

I've only just joined and have been trying to conceive for just one week now. Thing is, I'm not sure when my cycle really starts!

On 15/9 I got my Mirena removed, a week before which (~9/9) I had what I'd call my period (a very light, almost clear bleed for a couple of days).

But now I'm having a really heavy red bleed (4 days post-removal).

Is this my actual period?

When should I start checking for ovulation?

Any advice would be really appreciated!!