Can you have tiny pulmonary emboli and not know it? Would your body dissolve them if they were very tiny.

Yes. CT scans can pick up very time emboli that you may not notice. It is still unclear how to manage these small clots but most doctors would side with treatment since there isn't a great study that tells us otherwise.
Depends on size. And number. Yes, your body should dissolve them. You should be on anticoagulants to prevent more emboli. You ahould also ask your doctor to see if the source of these emboli could be located.