Re: The way others see you
You've done pretty well to keep three of you together up to 3rd kyu. I tested for my 5th kyu with five others, none of whom were still "with me" when I tested for 4th. Only one of them is still training. Inevitably, the three of you will diverge, and maybe now is the time.
At my dojo, Sensei starts thinking about having a grading when a group of people have enough hours or are close...then it's usually a couple of months before we get it together. In all, it's probably about three tests every two years, maybe less. What's the source of the expectation for you to test this time? Is it coming from the other two 4th kyus ("of course we'll all test together"), or from Sensei...or from you?