This is common, it is not an infection in most cases, and it settles quickly if you leave it alone.
Short answer: cool compress, no makeup on the area tonight, plain moisturiser. Most threading bumps settle within 24 to 48 hours.
Threading pulls hair out from the root. The tiny opening left behind gets irritated, and on some skin it reacts with small red bumps. Skin that is already sensitive, or that has been through a facial or a peel recently, reacts more.
A clean, cool damp cloth on the area for a few minutes. Plain moisturiser. Nothing with fragrance or acid. No makeup over the bumps tonight. Do not touch or pick. Hands are how a bump becomes a spot.
The bumps have white heads and are spreading after two days. The area is hot, swollen and painful rather than just red. You get a fever.
Thread five days before a function, not the day before and never the morning of. Do not thread within a week of a facial or peel. Ask for a cold compress right after, at the parlour.
Cool compress, plain moisturiser, no makeup tonight. Do not pick. Book threading five days before, from now on.
Usually 24 to 48 hours. Spreading white-headed bumps, or a hot painful swelling, should be seen by a doctor.
About five days before. That leaves room for any redness or bumps to settle completely.