If i had sex with a woman and 5 days later she told me she is pregnant is there any possible way it's mine? she took a home pregnancy test.

I'm suspicious: Some of the HPT tests claim very early accuracy. I myself would be a little suspicious. I personally would request paternity testing.

Unusual: The likelihood of someone having sex and then a positive pregnancy test 5 days later is very low. Pregnancy tests measure a hormone called HCG, which is produced on average 6 days after fertilization. The sensitivity of a urine pregnancy test is not high enough to pick it up that early. There are other medical conditions that produce high levels of this hormone, therefore she should see a doctor.

Unlikely: Implantation of a fertilized egg can take 6-12 days after ovulation. Pregnancy tests do not usually read positive until the mother's HCG, the hormone tested, has high enough levels, usually about the time of the 1st missed period. That she would test positive 5 days after conception is very unlikely. In my opinion you are not the father.

Unlikely: Usually home preg tests most accurate one week after missed period.