Late ovulation ? What’s going on ?

So I got my period for the first time last month 8 months postpartum. I got it 2 weeks after getting my first solid smiley.

I didn’t check for ovulation as I was travelling so I assumed I ovulated on vacation and was getting my period in the next couple of days. I decided to test and got an empty circle. For some reason I went back 20 minutes later and tested again and got a solid smiley. I tested the next day with an old clearblue opk and had a solid smiley

What does this mean? Faulty test ? Late ovulation? Change in cycle length?

I’m nervous because we weren’t safe 2 days earlier as I thought I was getting my period. Is there a chance I could get pregnant?

Thanks