If you show up to work but are sent home, so long as you are allowed to immediately leave, then you are not entitled to be compensated. However, if you show up but have to remain at work and wait, then you should be paid for that time as an hourly wage (i.e. non-exempt) worker. This of course assumes that there is no union agreement or employment contract that provides otherwise. Also, no form of legally actionable discrimination must be the reason for your treatment.