I think you have chosen an excellent topic and have a great targeted market to work with!
It is very common -- for all of us -- to doubt our work or that we will be successful with the product we have created. Its
only a mindset
Set out to succeed... and you will! I suggest that you join the on August 1st to help give you a push along towards the goals that you have with this project - many of us will be there and I'm sure you'll find much support.
Getting a few select people to review your ebook is an excellent idea! You might even try one or two trusted people on campus to look it over.