My last period was oct 1 I had unprotected sex from 8-17th oct and ovulated 20th oct. I am 21 days. I took a hpt on day 5, 9, 13 all neg what's wrong?

Clarify. I can't understand if you are saying you had a period last cycle or not. If the last time you had sex was oct 17th, and have a neg preg test now, then you are not pregnant.