Army Regulation against this?

I work at a clinic. Well,today we had Sergeants time training. I was released at 9 soaking wet and muddy to go to an App. at 10. Went home changed into PT's as told by my NCOIC didn't even get enough time to shower. Went to my App. and arrived at the clinic after my app. at 11:30 for lunch time. All the civilian Dental Assistants and Workers were there but none of the other soldiers,nor my NCOIC showed up. I found out that they were released to go home for the day after Sergeant time training and he himself went home also. My Supervisor (NCO) only showed up to clothes the clinic for the day in civilian clothes telling me "how I missed out" though I was ordered to go to the clinic after my app. Anyways,I got a call from one of the E-4s telling me how I was to work and wait till she got there to close the clinic. Telling me the NCO would call herself but her phone was broken. Then I asked her well how did u talk to her for her to tell you to tell me this,she responded oh her cellphone was only DEAD it's charged now. My NCO had told me when she got to the clinic that her cellphone is "broken" (kinda like they mixed their stories up)... There's a total of 6 military ppl that work at the clinic myself (PV2),3 Specialists,NCOIC,and my NCO. For some reason I feel like if I wasn't in trouble or doing corrective training there shouldn't have been a reason EVERYONE got to go home and relax WHILE I am the only working. Is there a regulation against this? Were they allowed to do this? Shouldn't my NCO have called me instead of a SPC when I know her phone isn't broken because the SPC told me it went from BROKEN to oh no it was just DEAD it's charged now BS? Something seems unligitt or they wouldn't have made up a lie about a cell phone? Right? I need help. I feel like they are running over me because I'm a PV2 and they NEEDED a military personnel to stay in the clinic to make sure no civilians had over time,but shouldn't my NCOIC or NCO taken care of that in a better manner?
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Have you never heard of rank hath its privileges ? Someone had to stay, they decided it would be you. Thats why the military has privates, to take all the crap jobs. Just get over it, soon enough you will be an E-4 and get to tell someone else they have to stay.
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