communication and comparison

so here is the situation. I am in the communication with my lead, amazing guy, he asks me why I implemented these features in certain way. and I have done pretty good job. but when I explain I could hardly understand my self ( it happens sometime ). somehow I become submissive in conversation. like really start to play defensive. while on technical level I should be dominating.

it happens while I communicate with other peoples. when I clearly know things are sidetracking I am not good to assert strong statement. I feel like I somehow hurt person in front of me.

behind the scene some comparisons are also happening in my mind where sometime I am putting person in front me on higher position.

I am sure this is the struggling period where i am actually developing my skill to communicate properly. I am not running away. and in a month or so I should be able to see clear progress here.

but I need to put full attention while I am communicating. and instead of just replying also make sure i am able to see the whole context as well, and understand question clearly.