The lesson of 'just one more trade' with $NVDA

I had a decent run last week, mostly scalping $NVDA calls and puts. Market was choppy but predictable within a range, and I was feeling pretty good about my read on the pivots. Had closed out the day up a solid amount, more than my average target, and probably should have just walked away. But I saw $NVDA breaking above a key resistance on the 5-min chart into the last hour of trading, and the momentum looked strong. Convinced myself there was 'just one more scalp' left in it.

Sized up slightly, thinking I was still being conservative, bought calls. The stock popped a bit more, but then quickly faded, trapping new longs. My mental stop, which I didn't actually set on the platform because I was 'watching it closely,' got blown past as the price reversed hard. Instead of taking the small loss when it first broke back under my entry, I held, convinced it would retest. It didn't. Ended up giving back a good chunk of my day's profits on that single impulsive trade. The lesson, again, is that once you hit your goal, or even exceed it significantly, protect those gains. There's always another day. Greed, even subtle, is a hell of a drug.