Paranoid my breath smells all the time

It all started when I was like seven and my mom would send me to brush my teeth because she said it smelled. Ever since then I started brushing my teeth three times a day and I'm still paranoid twelve years later.
I can't talk to people up close, I always try to cover my mouth when talking or I do it far away from their faces. I can't even talk to girls when they get really close to my face, I usually fake a pose or something with my hand and avoid it. In these twelve years nobody has ever told me my breath smells bad but I'm very self conscious about it.