Period gone for 2 days and now yellowish brown discharge

I had my period, it started on the 19th and ended on the 22th. But I was bleeding/spotting 5 days before the period actually began.

Now I have yellowish brown discharge.

- Is it still from my period?

- Or infection or something else?

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BONUS QUESTION

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If it is an infection, I have taken blood yesterday but didn't really tell the right reason why and also said check everything.

- Could they find that I have an infection?