Try licking your wrist, leave it for 3-5 seconds to dry then smell it.
For you I think you might be having a build up, most bad breath comes from the tounge (about 80%)
you could try a tounge scraper. Or a spoon.
and brush twice a day, also not just your teeth maybe your tougne too, I also reccomend the colgate 360 toothbrush, it'll help your bad breath too.
Try also them portable breath sprays.
Also remember a lot of people fear this also.