Am I being bullied because of race and can I be drug tested and breathalyzer on my day off for suspi

I started a job a couple months ago in a kitchen at a children's hospital, I was the only white person everyone else wad black and related, I had heard 1 white girl worked there at another time but claimed they bullied her than fired her saying she was lazy, I believe I'm bullied constantly doing others work and talked down to, some come to work clock in then go home while I do their work, I turned someone in on the compliance hotline, next thing I know I'm being called in on my day off to do a suspicion and cause drug test and breathalyzer, I passed the breathalyzer but if I chose to can I not drink on my day off, I was positive on my urine test which I knew I would be because of my ADHD meds, I brought my prescription but they have to send it out for a second test, I was called several days later by a lady at the lab not the MRO and she asked what prescriptions I take and to send a picture of my adderall label which I did, after that I was wondering why she asked and not the MRO what right does she have, I asked her how long before the doctor contracts me she said about 24 hours it's been 72, so I'm still suspended from work, do I have any rights here, I'm already going to be embarrassed going back to work.