I just need to do as you suggested and rework examples and not move forward in the book untill I feel comfortable with what the current chapter has taught me.
That's the idea... if you can make changes to the code, no matter how small, and still have a working program, the odds are that you understand it... For example: Almost every C book starts with "hello world" as the first example... make it say something new on a second line.
Programs are basically solutions to problems... One of the first lessons I learned when starting out is that you can't solve a problem you don't understand.