It is too early for your pregnancy
to be detected by ultrasound
. It is seen on ultrasound only after 6 weeks since missed period.
Your urine test should have been positive by now. If it was faintly positive then you can either repeat the test with a fresh morning urine sample.
A blood test
for beta hcG
can confirm pregnancy in the best way in your case. It comes positive even before urine test and ultrasound.
Sometimes due to low hormone levels , the urine test comes faint positive. It might also be an indication of abnormal pregnancy that is one which is outside uterus
So you have to get your ultrasound also once you complete 6 weeks and if your repeat urine or blood test comes positive for pregnancy.