Nothing we can really do to get you back on track. The way I control my tendency to procrastinate is using something like Astrid Task Manager, and assigning myself tasks each day. I don't do anything fun until I am finished with everything. The faster I work, I know I'm getting faster to actually doing something I enjoy like programming or games.
I actually understand your feeling, I used to be a perfectionist and I started getting that senioritis, but Astrid and constantly reminding myself that I'll end up in the back of the unemployment/soup kitchen line if I don't push myself helped.