I have taken my urine test and it showed negative.and my last period date was 28 of sep and yet I'm not in period, and my hcg report is 18.10 may I know what I am to

It may be too early yet to get a positive result. The quantitative test gives the actual number, and an 18 could be a very early pregnancy or perhaps a pregnancy that resulted in an early loss. It could be the level your doctor uses as a cut off is a bit higher and you are not pregnant.

Did your doctor say anything about waiting another week or so and testing again of no period? If you are pregnant, the number would have course be higher with the next blood test.
See if this period shows up. If no period, try another home test in about a week.