I recently go myself a airbrush with compressor, double action, etc (don't knw the type, but from what I've seen on the net it closely resembles a Badger 150). I painted with it a few times (3x), cleaned it properly and now it doesn't work anymore

. When I tried to paint something, air bubbles up into the paint jar and nothing is coming out of the nozzle, and on when it does, it spits the paint out, not with an even flow, just short bursts.
What is wrong

I just had the thing for a few days and now it's broken.