CNA before nursing school

OK so I have a question.. im normally one to just believe all patients are my patients.. however it was the way the facility did it.. this facility keeps up nonsense and because I could read that I started my own medical uniform line for my own financial security as well as to prepare for college. Recently I started to wear the pants and the top however I wouldn't sell to anyone in the facility.. a lot of times this one clique talks down to me but I don't really respond bc I know my future plans are greater than a CNA.. Thursday the nurse comes to me between 2:17-2:40 when the shift is over at 3pm telling me I need to shower a patient that's not even mine!! I responded saying it's not my client and it's too late to be providing a shower not to mention I have not taken a break.. she responded saying they're all our patients and she's writing me up because im being insubordinate.. this same nurse wrote me up about a month or so ago saying I didn't do what was asked when indeed I did .. so I'm assuming it's targeting .. however setting clear boundaries is necessary. I asked where is her CNA why can't she shower the patient her response was we asked her to do something else .. meanwhile I watch this same CNA at the desk with that nurse .. so I said I'm not doing it at 2:40 when I get off at 3pm without taking a break..and she went off making up lies etc. when leaving the facility I asked a worker in a high position is that even heard of she confirmed the patient has or had bed bugs recently.. and they may say its all our patients.. so technically they would've sent me into shower a patient with bed bugs and was not planning on telling me .. aaaand she's not my patient.. so it's probably a good thing I set the boundary and said no..

Long story shortened I'm a CNA required to do someone else's patient while they stand at the desk all day .. asked at 2:40 to shower a patient..that isn't my patient.. my response why hasn't the person who had her showered her all day .. response was we asked her to do something else my response the entire shift? They're response.. your refusing .. as they all stand at the desk .. what and how do you respond to this