I had a beta hcg blood test resulted 17.4 from 2 days my last period was in 14 February I wantto know if I am pregnenet or not and how can I be sure that I am pregnenet please ?

What did your doctor tell you when you received the results? Will you be going back for another blood test to see if the numbers have increased? The elevated level suggests pregnancy, but it seems unusual that you would not have been told that and are asking what it means. Your doctor should have discussed the results with you.

Or are you asking how to know if you are still pregnant?

If that is the case, you could try another pregnancy test and see what results you get. Your doctor would have told you when to come back in for your next prenatal exam.