If you've tested negative then don't worry about it. It won't be a false negative as they actually culture the bacteria from the swab you provide. If there is no growth then there is no bacteria present. A baby born to a Mum with GBS pos can be severly affected by this bacteria. It can affect hearing and sight amongst other things, but it's not a black and white thing. Some women who are GBS pos will choose not to have the antibiotics in labour and go on to deliver a perfectly healthy baby. If you are GBS neg than just put it out of your mind you have nothing else to do now other than enjoy the last few days of your pregnancy and wait excitedly for your precious bundle to make an appearance.