You have to be aggressive during your training. It's just like when you're a nursing student - if you'll follow along and watch - that is exactly what the nurse will let you do. When I was going through my clinicals in school it was always a little weird walking up to someone I didn't know from Adam, especially when they didn't make eye contact or acknowledge my existance, but I would always be really assertive and say, "I don't know how much you're comfortable with letting students do, but I'd like to do anything you'll let me." I was the first and only student in many clinical rotations to get hands on experience doing many skills...hanging IV fluids, starting IV's, passing meds, flushing feeding tubes, etc.
When it was time to do my final semester clinical I did the same thing when I met my nurse. She basically stood behind and followed ME. Thank goodness because of all the experience I got during my final semester, I went into the job force feeling pretty ready...although you're never REALLY ready.
The next job you go into...act confident...even if you're not..and you won't be. Nurses are going to be "iffy" about giving control to someone who acts like they're not confident. Even if you have to ask 500 questions while you do what you do...YOU should be the one doing it. At least at the end of the day, your preceptor can say, "she passed meds. she did the assessments. she called the doctor. etc" Even if you needed a lot of guidance...as any new person does...it sounds a whole heck of a lot better than saying, "she watched me all day." You just have to get in there and do it. I can watch a video of how to do something 500 times and hear about something in lecture 4000 times, but until i do it ONCE..i don't know what I'm doing. I've been known to tell preceptors that very thing.
Four days isn't a whole lot for anyone, but you'd be amazed at the difference between four days of doing vs. four days of watching.