Work Ethics (Long)

[InstaCall]

I just wanted to share with this to you guys and see what ya'll think. So i work at this company where we sell tvs to customers and get commission off of it. So this monday i was scheduled to be off at 5:15 pm. A couple came in around 4:50 so i started answering their q's. around 30 min later they wanted to go to frigde dept. cuz they thought they wanted to take care of that first, they told me to hold up. I said ok. It was around 5:10 and one of my co workers came up to me and went " so you leaving in 5 right?" i said I dont know about that, i still have customers. He goes you cant do that its not fair to us. I said dont tell me what to do and walked away. by 5:15 i took my badge off and got off the floor, not helping anybody jus waiting on my former customers. I guess my co worker calls the manager, she walks up to me and says you cant be here even though i was clocked out and took my badge off. Was I really being unfair or just protecting my rights (sale) ?