I have 3 days left till my period comes and the condom broke but we instantly changed to a new one. i think only a tiny bit of pre cum got inside but thats about it. should i still take plan b? what are my chances of getting pregnant?

Sex: "Precum" is premature ejaculate and it contains sperm. Therefore, you can still become pregnant. There is a 3 day window for plan B to work. Plan B can prevent pregnancies up to 3 days after sexual intercourse. Consider discussing this further with an obgyn/women health specialist ASAP or go to the drugstore that sells OTC Plan B. Consider STD testing too.