can I sue my employer for consequenceing me for abiding by the same Union policy they failed to obse

Last week I was sent for a drug test on a Saturday because they couldn't give me a definitive answer as to why they were sending me first answer they gave me what is it I'd violated some safety protocol however every other operator that does my job has done the same thing so that's got squished the second one I was told that people are coming in saying I was ",acting hi" which constitutes hearsay in the third one was the
Yvimed random get in absolutely no way shape form or fashion was the protocol for random drug testing. That was last Saturday I refuse to test until such time as I could speak to the plant manager who is actually the one that ordered the test in the first place. The following Monday I was unable to gain audience with the plant manager so I had to go through HR still asking for a definitive answer or reason as to why I was being told I had to take a drug test they cut me off refused to discuss with me and basically let me know that I can either comply or be fired. I could have gone through an evaluation or retake the test in which case I told him I would take the drug test .I did pass it. I was sent home from Saturday until Wednesday when results of my test came back and I was clean I was being allowed to return to work as normal and I might add that the 7 to 3 and 11 to 7 shift there's two people that do the same job I Do by myself on 3 to 11. I'm not complaining I prefer it that way but they're worried that if I can do it by myself that they're going to be expected to. I do tend to work a lot harder than a lot of other folks and I've had several other employees come up and tell me to stop doing it because if corporate sees me doing it they're going to expect them to do the same thing. And the fact that I'm I rather attractive female and work twice as hard as just about anyone else there only seems to add insult to injury. I've been allowed to be at work all week until an attempt was made to try and collect wages for the time that I was off now suddenly yesterday they call me in send me home again telling me that I need to go and be evaluated by some medical facility give me the okay and clearance go back to workin Claiming that because I didn't submit to drug test on the day I was requested Union policy dictates that I have to have some medical evaluation to clear me to come back to work. If the conditions under which the drug test was requested doesn't abide by Union policy and when I tried to use the union policy to defend myself I was cut off yet they want to turn around and use Union policy to consequence me when they didn't observe or follow Union policy governing the way drug tests are administered yeah they want to use Union policy to consequence me for the so-called infraction I'm guilty of.
To sum it up they refuse to accept Union policy when i used it in defence for their blatant Failure to observe Union policy regarding drug tests,yet when I didn't do it on the day they requested it they're using Union policy to consequence me and refused to allow me to use Union policy again to defend myself.
Not only have I not received any pay for the time that they sent me home but I also, strongly feel that I'm the victim of a witch-hunt for lack of a better term and I need to know what options i,f any I have available to me.