ondai, your swing looks a bit "handsy" and you look as though you are picking the club up steeply. at impact you are coming out of the shot. it sounds as though your shot was "slappy". this can happen with these faults. saying that your swing is not bad for a beginner. with the right tips you will see a marked improvement.
try working on a slightly slower backswing without picking the club up too steeply. try and rotate your hips a bit more. at impact try and stay with the shot, dont look for the ball flight too soon.