There was chance that I could make out my 2 points if I stick to a 1518 limit order. However, most of the time, the future market stays below 1516. Record my emotion here
1) right after I cut at 1516, I felt a lot of pain. I was so sure that market will go to 1518 and I could get out at even.
2) after a while, I let it go and felt nothing.
3) Now, realizing that I could get out at 1518, I still feel much better with the cut.
It seems the stop loss pain is a short pain after all.