There is no need to do another HIV test. The two main HIV tests we use in BC Canada are a rapid test were you test a drop of blood from a finger prick and get an instant result and a test were a blood sample is taken and sent to the lab. Both of these tests would give you a final result by 3 months. A negative HIV test at 30 weeks means that HIV did not pass to you from that exposure.
Let us know if this does not answer your question or if you have any more questions.