$NVIDIA(NVDA.US)Personal summary: After being taught a lesson in the A-share market, I started trading US stocks in October, just before the US election when the market was hot and sentiment was high, with Tesla hitting new highs. I saw in the comments that Tesla options were profitable, so I made a small position in options despite not understanding them. I was inexplicably exercised and felt uneasy, but luckily ended up with a small profit as it was below market price. Later, seeing NVIDIA's market uniqueness and a blogger buying one, I greedily built multiple positions before earnings, expecting a big rally. But my lack of knowledge cost me—despite two metrics beating and one missing expectations, Wall Street lured in buyers before grinding down options. Unable to sleep until expiration, I finally cut losses during the session, surrendering all profits and some principal.