If you want to be sure, get a blood test.
I took my test on Wednesday after realizing I was 4 days late and it was positive! You should be able to take one now using your first morning urine, as that is when your HCG levels would be at their highest. I noticed that you are 14, why are you thinking you are pregnant at age 14????
You can take a test now with First morning urine :) x