I am not planning to give excuses. I was thinking about explaining how much the bad score impacted me and motivated me to study harder.
No. A 2 won’t affect your admissions that much (if at all). Additionally, I really think no matter what you write it will come across as an excuse. The smart thing is to just not draw attention to it. Let the rest of your application speak for you.
I don’t think you need to send the 2? IMO probably not worth explaining it.
No need to submit AP score to UC