4-leaf clovers are the imprints that were on the pill, do you remember what color they were?

Just like green butterflies, Pink Penguins, shit I've even had one with a Mercedes imprint on it haha.

And being that you were unable to sleep, it was most likely speed based, either meth or coke. I personally prefer heroin based X becuase you can relax and just chill out, usually speed based X is for Raves so you can get up and dance and feel all over everyone. I can't say that I don't enjoy raves though.