Only the matter falling into it would increase its mass - but because it's so small (on the order of the size of a proton at the moment it disappears entirely), it wouldn't interact that much - directly. Ordinary matter would seem like an immense emptiness to a microscopic observer following the micro black hole on its journey.
The zone of disruption surrounding the micro black hole would actually tend to repel things.
Regards,
If I may ask, is this a particular field of study for you?