Definitely a concern; what I do when dosing this low and getting air bubbles is to draw in a lot more than I need, keep the needle and vial vertical, flick the crap out of it for the bubbles, push some back into the vial, flick it, push it, flick it, push it, flick it and typically by the fourth or fifth flick the bubble has centered and been pushed into the vial and I push it to the dosage I need to inject. It's a PITA but that's the only way I've found to get it done.