Need some help

So i guess i need some advice on something. It has nothing to with love or personal stuff. It has to do with my job. I will tell you the story first. So this week i went camping. I had booked off Friday, Saturday, and Sunday. When i looked at my schedule last week my boss had booked me in Friday and Saturday i was not able to see if i was working on Sunday cause that was coming out the next week. so i found two people to take my Friday Saturday shifts. Then last Friday the day i was leaving i found out that i was working on Sunday. so went camping for Friday Saturday and then my parents had to get me form the camp site at 9 Saturday night. I went to work on Sunday morning. But on Friday i said to my parents was just call work and tell them i could not come in. but my moms reason was "we can not just leave them hanging" but to me everyone has left them hang so many time. The other thing is that i have worked there for a year and 4 months and i have yet to miss a shift. so that is one this and the other this is that i am unable to work on Tues and i am working tonight. so basically my boss has screwed up my schedule. And this kind of stuff has been happening to everyone for along time now. so what i want to know is i want to quit. but is this the right thing to do. oh ya i am a cashier at a grocery store.
well thanks for your help.
Rebecca
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