Wait, Was That A Kairotic Moment?

Since we've learned about kairos in class, I've found it so interesting, although I cannot exactly explain why. I guess the overall concept of taking advantage of an opportune moment is intriguing to me and more importantly, how someone decides to approach said moment. But for this blog, I wanted to explore the concept of "missing", if you will, a kairotic moment. What happens if a moment is there but you don't take advantage of it? Is it no longer a kairotic moment if you decide to address it hours, days or weeks afterwards?
I understand that there are some kairotic "moments" which are longer lasting than being merely a moment. For example, I'm sure if Rosa Parks refused to give up her seat on December 2nd instead of December 1st, the Civil Rights Movement would have still proceeded as it did, regardless of the one day delay. However, there are those moments where something happens and we might not say or do anything in the heat of the moment but later, we reconsider the situation and realize we should have done something. Then, if you do something later, is the moment still kairotic? Here is a personal example to really capture what I am trying to get at.
So lately, my roommate and I have not been getting along very well. We don't speak to one another when we come in and out of the room and things have just been tense. Over THON weekend, my younger brother came to visit and while he was here, my roommate barely spoke to him and came across rather rude. My brother felt so uncomfortable (as if she really did not want him to be here) that he would find any and every reason to leave my room. At the time, it really bothered me that my roommate treated my brother this way. I believe, regardless of whatever problems she and I might have, she should not take those problems out on my brother. However, I never mentioned anything to her about how her rudeness towards my brother made me upset. Now, it's been about 2 weeks since my brother has been here. Since I let so much time pass, have I missed a kairotic moment by failing to address how I felt when the situation was actually happening? Would it be awkward or even unnecessary to address the problem now?
I think it's interesting to consider how much a situation changes when we allow time to pass and how we deal with missing a kairotic moment. It seems like often times, if we don't address a problem at the moment, it's no longer important to us some time later. Ultimately, we missed the moment so we have to move on. But I'm wondering, is that really the case? Can a moment still be kairotic if we let some time pass and then decide to address it?