Hmm, I don't know what to say other than make sure to shake the paint well? Lol, and yes...
BE SURE TO ALWAYS CLEAN YOUR AIRBRUSH AS SOON AS YOU ARE DONE!!!!
I also learned the hard way... and lost quite few brain cells to the acetone that I had to soak it in for an hour... not fun. That is precisely why I strongly recomend the airbrush-ready waterbased paints for beginners.