Late Period?

According to my app I am 2 days late. I never start this late in the month.

For back story I had a miscarriage in September. I had my cycle on the 17 of October. Usually before my miscarriage my cycle started on the 14th or around there.

Anyway, I am two days late according to this app, but other apps say three or four.

Either way, from any apps I am late.

I took a test this morning and it was negative. Although it was a blue dye test and it’s hard to read. Could my miscarriage have just really messed up my cycle?

I’m nauseous everyday, bad heartburn, I could sleep all day if I could, I have headaches, I’m bloated and I just overall do not feel good.

Are the blue dye tests really less accurate? What’s been your experience with them?