Tips for improving bout-awareness and tactical decision-making?

Hey, I've been fencing épée for 3 years and I also regularly compete at state-level tournaments. I definitely want to improve in order to make it into the national squad and also compete internationally in the future.
Now my question: I wanted to start keeping a kind of journal about my bouts, mistakes, and what I could improve a while ago. So during a bout, I try to understand: What are my mistakes? What can I do better or avoid next time? But somehow, it doesn’t quite work. Sometimes I don’t know exactly what I should be focusing on. Why did that hit happen? Was I at an unsuitable distance / did I let myself get drawn in, or was parried?
Especially when my opponent makes fast and good attacks over the blade, I find it difficult to perceive what just happened and what I could have done better. Sometimes I know why a hit happened, but I have no idea what I could have done differently.
Im more defensive and sometimes I don’t dare to do certain things. And even when I haven’t had a lesson for a longer period of time, I feel very insecure.
 
Could anyone give me some tips on journaling and on generally being able to perceive what’s happening and switch tactics during a bout?