Can brown discharge on the 3rd day of a break in contraception be pregnancy?

No, it is not a sign of pregnancy. The brown discharge that appears during the break after 21 days of taking hormonal contraceptive pills is usually associated with the so-called withdrawal bleeding. This is a normal reaction of the body to changes in hormone levels caused by a break in taking the pills. This discharge can vary in shades, from pink to brown, and is usually less abundant than regular menstruation.

The brown discharge is often the result of older blood that has been in the uterus longer before being excreted, which can give it a darker color. This is typical and should not be a cause for concern if it occurs in between cycles of taking pills.

If you have regularly taken the pills at the same time every day for 21 days, the risk of pregnancy is very low because birth control pills are very effective when used as directed. However, if you have had any interruptions in taking your tablets, missed doses, vomiting, or diarrhoea that may have affected the absorption of the medicine, your risk of pregnancy may increase.

If in doubt or if the brown discharge persists for a long time, it is worth consulting a doctor or gynecologist. If you are concerned about the possibility of pregnancy, taking a pregnancy test can also help dispel doubts. If you are not able to make a face-to-face visit, I attach a link to the online teleconsultation:
https://www.gdziepolek.pl/telekonsultacja/z-ginekologiem

I also encourage you to read materials on similar topics:

https://www.gdziepolek.pl/artykuly/jak-prawidlowo-stosowac-antykoncepcje

https://www.gdziepolek.pl/artykuly/jakie-leki-oslabiaja-skutecznosc-antykoncepcji

https://www.gdziepolek.pl/artykuly/czy-jedzenie-i-picie-obnizaja-skutecznosc-antykoncepcji