why did I stick to long term investment?!

I stuck to long term investment because it started to seem when I was losing on a stock I would get scared and sell right away and with in a couple days the stock went up. For example when I bought 84 shares of sopa I sold 55 for 10.51 (bought all for $4.41) and the next day it went up and it seemed as if this was a pattern...I could have doubled my money and instead I got scared and sold majority u of the 84 stock leaving nyself 29. If I'm able to invest I would say invest long term because those little gains are awesome but if your patient you can not only double your money but make multiples. patience pays.