Yesterday I opened a Put Calendar on LVS:

Apr / Jun 70 puts for a cost basis of -2.63

I attempted to enter an Apr / Jun 85 and ended up getting a Mar / Apr 85 for -2.10.
I realized that this was not the right order after hours. What happened? LVS gapped down and I couldn't get any more then 1.05, so I incurred a 50% loss on this screwup. Ouch.

Just reminds me that although I've gotten 1000% better at this, I still need to take my time and double check everything I do. Everytime I do it.

MdrNate