I cant follow rules

Bought VEEV yesterday on day 2 earnings at 4day EMA. Had 90$gain on close, today it opened and spiked and i had unrealized gain upto 300$ plus but didnt put a stop loss or had an exit plan.
Market then turned red and it kept tanking and tanking, instead of 300 gain i had 500+ loss around low of the day, finally it turned updward and currently my loss is around 250

the mistakes i made


1)I didnt have a defined stop loss, your stop should be present and keep raising it as the trader goes

2)I didnt exit at the morning spike, I should have at-least partially

3)I should have at least stopped just above breaking even, I didnt

4)I had a change to get out breaking even after the initial on midmorning spike, I didnt

  I went in too big, breaking my rules, and had 18000 position, it shouldn't have been more than 6000