You likely won't test positive 5 days after. The egg likely hasn't even implanted fully yet.
It's not so much about when you had sex as when you ovulated. Sperm can live in the uterus for up to a week. Even if you ovulated the day you had sex 5 days is too soon. The earliest I've gotten a positive was 10 days after ovulation which for me was 27 days after the first day of my period. Some women get it as soon at 8-9 days after ovulation.
I found out 4 weeks later, the day my period was due with all three of my pregnancies
I found out 5 weeks later
I Found Out 6 Weeks Later