If the dust got in there on the last coat of say three coats, you have a chance of sanding it out with an auto detailer clay bar leveling the surface.
If they are deeper, say into the first coat, take an Exacto Knife and dig the dirt out with the least disturbance/damage you can. Put a dab of paint in the void. Try not to overfill, keep the dab of paint as level as possible - it will save you a lot of time. Once cured, take a clay bar to level the patch of paint. Once the paint surface is back to true the repair should not be noticable. This is tedious work - but it can be done. The key is to go slow and not rush it.
Edited by Gtractor, February 20, 2014 - 08:57 PM.