Failed first nursing check off

Today we had nursing check offs for our first term that included vitals, cbg and immunizations and I passed vitals and immunizations and sadly failed cbg(the easiest one) because my nerves got the best of me. I was so nervous that I went to poke my partner and realized the cap was still on, so I took the cap off and went to poke again without recleansing the area and my instructor had to stop me and tell me I didn’t clean the area so I couldn’t proceed, so I got a no pass. I know that I made a mistake and shouldn’t have passed for that because the instructors told us in the beginning that if they had to stop or prompt us that it would be a no pass. My issue is that later in the day when we were doing immunizations a girl in my group was going to give the shot after she repeatedly touched the cleansed skin with her gloves and my instructor stopped her and ASKED her if there was anything she should do before poking her, so then she realized her mistake and recleansed the area and she still passed her. I just feel like it wasn’t really fair because they said they aren’t supposed to prompt us and if she had stopped and prompted me, then I probably would have passed. Just seemed like unfair treatment to me and I’m a little hurt and confused by it, but I don’t want to animosity towards my instructor. Any opinions on the matter? Also, I redo the check off in a few days, so tips on how to remain calm would be greatly appreciated! Thank you. I just feel like an idiot and so embarrassed that I failed the easiest thing.