Coke is no Joke. Unfortunately, the answer is yes and so is the possibility of death from overdose. Anyone considering experimentation with this drug should seriously reconsider and stop! In some succeptible individuals receptors in the brain (as with nicotine) can cause addiction relatively quickly after use. The physical need is surpassed by the psychological need and your hooked. Be kind to your mind!
Yes. Once is too much for recreational drugs - some experience is not worth knowing.