No period , negative HCG blood test ? What gives ? Anyone else been through similar experience ?

Hi ladies , I really would like to know all your stories related to this issue.

So I stopped taking the pill( lessina) a month ago , and started having sex every night with my husband cumming inside of me , even during my ovulation, I am now five days late for my period , I had an hcg blood test two days ago and it was negative...I definitely feel I am pregnant though. Also I have never missed a period unless I was pregnant . have any of you experienced something similar ? Did you ovulate late ? When did you find out you were pregnant after getting negative HCG blood test results ? Please let me know .