In fact it could have been implantation bleeding since you again had sex on July 4 without taking plan B again.
You need a blood pregnancy test.
Home tests are accurate when your period is again due, but that might have been disrupted.
Take a home test again.
In addition, call your doctor.
Bleeding at this point can not be assumed to be from plan B.
It can be, but any hormone disruption can do this.
So can a period.
So can thyroid disease, liver or kidney problems, stress, weight loss or gain, etc.
Not simply a question and answer internet situation.
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