Took a pregnancy test on July 24th that was negative

Period start day was supposed to be July 27th

However I started bleeding on July 25th

I bled for 4 days

Stopped bleeding for one day

August 6th started cramping pretty bad at night.

August 7th wiped with brown blood through the day and took a pregnancy test that was positive.

Miscarriage?

Chemical pregnancy?

Implantation bleeding?

I have an appointment scheduled for Monday at 9am but want to get others input!!