No there is not such book for you*...
You are the professional...and you are the only one that can give the answers. If you don't know what is more important, no book will help you and you are in the wrong job.
Having this said, I wish that there more like you asking for advise... to help you in the time management field where most people need help.
There are many methodologies but if my feelings about your need are right, all you need is two softwares and alot of discipline: MS project(or something similar) excel(or other spreadsheet)
Make a detailed plan - detailed enough to tell you at the end of each day if you fell short or exceeded your plan. But not to detailed - you need time to work and not just toy with dreams and plans for the future.
in the excel make a log: task ! plan hours ! actual hours
in days where you accomplish less then 90% of your actual planing - are very hard days with a lot of over time - you want to go to sleep and fix everything tomorrow -don't! Spend an hour to log what went wrong... phone calls, meeting... everything.
You have to problems
1. You don't know to make good estimations.
2. you jump from one task to another loosing valuable setup time.
You will be late in the next project as well and that is unavoidable... but if you will understand where you loose time. You will make more realistic plans and become a better manager.
*If these thumb rules are not enough - the PMI.org has good website, good course, good book and good people with their PM certification- you can find such expert or become one.
But I really believe that when a professional looks at hard data he can make decisions:
1. I can't speak 4 hr with that client everyday without charging him for the time.
2. That task took me way too long - I need to concentrate, next time I'll do that on the weekend after everybody is gone... shut down the cellphone and finish the job in half time
etc...
- I strongly advice you to find someone that will teach how to use project management correctly, mainly - how to move unfinished work to the future - it's crucial that you will have the real picture of your status and not just have a list of tasks (marked as finished/ not finished) - You will learn alot from analyzing well maintained plan (well not a plan anymore - but actual work!)
Good luck
Asaf