Brief Answer:
Not black spots, they seemed to be chemical burns, Dermatological check-up recommended without any further delay

Detailed Answer:
Hello there,
Welcome to 'Ask A Doctor' service...
I've gone through your query in details...
I can understand your concerns...

I've checked the attached image and it seems like some chemical burns (could be secondary to Dettol application). Please note, Dettol is an irritant to the face and you should never apply it over the face unless specifically advised by the medical doctors.

For minor cuts in the face, only aftershave lotion is sufficient to apply...

Please refrain from using Dettol in face henceforth, just keep the area dry all the time... Apply some Aloe-vera lotion very very gently, don't scrub at all, avoid direct sunlight exposure over the area for the time being...

It's recommended to seek a Dermatological check-up for routine dressing over the area and follow-ups accordingly...

Let me know if I can assist you further.

Take Care
Kind Regards

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