Pregnant? Thoughts?

So according to this app, which has been very accurate for me over the last 2 years or so...

I ovulated on the 15th

Had unprotected sex on the 18th (he supposedly pulled out and I took the morning after pill)

Have been light spotting dark brown color since the 24th (about 3-4 days)

Period is due on the 29th

My breasts are super sore. The last time they were this sore, I was pregnant but had an early miscarriage. I’m paranoid I might be pregnant again, and am terrified of miscarrying again. Almost exactly 1 year after the last one.

Thoughts? Am I just being paranoid? Or could I be pregnant?