Violin Practice issues?

I've been playin violin for 5+ years, and I've just started the bruch violin concerto in G minor... I've noticed that I haven't been progressing as fast as I should be, and I finally found the source of my problem. I'm a terrible practicer. It isn't my teacher, who is a graduate from juliard, and it isn't because I lack any natural talent. So I was just wondering if any of you had some good tips on how to practice?