You are correct that the antibody test for HIV takes months to become positive. Unfortunately, the rapid HIV test is just a faster method of detecting those antibodies. So while the result so the test will come back faster, you can't have the test done any sooner.
Since you were possibly exposed to HIV 4 weeks ago, you are nearing the end of the window where you can develop the acute retroviral syndrome. This is an illness that 90% of people that received the virus will get between 2 weeks and a month after exposure. Symptoms include fever
, night sweats, enlarged lymph nodes, sore throat
, muscle aches, a rash, and several other episodes. People who get the acute retroviral syndrome often say they thought they caught the flu. While the absence of these symptoms does not rule out HIV transmission, it does reduce the likelihood that you did get it.
I suggest that you schedule an appointment with your primary care physician
. He or she can take a detailed history of any symptoms you may have and perform a physical exam, focusing on the possible findings of the acute retroviral syndrome. The two of you can also discuss measures you can take to protect yourself against HIV. In a couple months, you can have the HIV antibody test. Good luck.