I feel the start of this as well. I have a very bad habit of letting things sit until last minute, which comes back to bite me later. Additionally, I feel like a lot the quality of my work dropped due to this as well, which is generally a bad thing. I usually attempt to make myself work in smaller portions at a time and set my own due dates before official due dates. Trying to utilize planners and organize your tasks is a very good start to breaking out of any disorganized habits! I'm glad it's been working for you and you can get a lot of satisfaction from it, maybe I should try it out too!