Film your flights. First question is hard to tell without film, but it was likely a stall reversal or an overshoot setup.
Second question...Here again, film is your friend. All the altitude and speed for every player within range is recorded. If you're doing 200mph at 5K, and I am doing 490mph on the deck, who has more E? Your F4u4 can probably zoom another 2K. My 38 can zoom about 7.5K. That means I have more E than you.
I commonly go low, or stay low to mask my E state just so I can catch someone trying to go back up to their perch. If you have a film to review you can usually see where and how you misjudged another planes E state, or how that plane bypassed your situational awareness and surprised you.