Brief Answer:
These are pimples.

Detailed Answer:
Hello,

These are pimples.Such pimples are common in forehead region and at your age.

Secretion of sebum is more in the region of forehead.Sebum is sticky liquid secreted by skin glands to keep it from getting dry.Increased secretion is the reason ducts of glands get blocked causing such pimples.Also at your age hormonal changes play role.

They look filled with minimal pus.

Few things that can help are -
-local antibiotic cream
-keeping the region clean, wash face thrice daily ,
-use creams with resorcinol, benzoyl peroxide, salicylic acid, sulfur, retin-A and azelaic acid , drink adequate water, take steam.
-Drink adequate water.
-Avoid being in extreme climates.
-Avoid dehydrations.
-have balanced diet.
-Limit, if there is any stress.
-Sleep well.
-Dont let sweat dry on the skin.

This will help reduce the pimples, if they persist then you will need treatment with oral antibiotics.

Hope this helps.Please ask if there are doubts.Regards.

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Brief Answer:
6 weeks is time expected.

Detailed Answer:
You will have to take treatment for six weeks.In most cases symptoms and pimples resolve by then.

In cases symptoms persist, one has to consider taking oral antibiotics.Regards.

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