stressful work situations

I had a crazy weekend so I am going to make separate posts. The first one will be about some stressful things so I can get it out and not think about it anymore.

Around 3 weeks ago I found out my sunday school class was taking a girls trip to Austin the night of Aug. 6th through all day the 7th. I had already requested to have off 6 days at the end of august for the big anniversary weekend so I decided I would ask off for this and if I didn't get it that wouldn't be a big deal. Well the manager who does the scheduling gave me off saturday and sunday so I was like maybe she got it kindof mixed up because she does that a lot. So I asked this other manager one day if it would be possible for me to give my shift to this girl jessica since I took her shift a couple weeks ago when she couldn't come it because she lost out on those hours. So he approved it and signed off on it on the schedule which makes it official.
Well after that I went and paid for the trip not thinking it would be an issue at all. A couple days later I go to work and the schedule that had his signature was gone and it just had the original schedule. I figured hmm thats weird but maybe somebody moved it. Then one day I worked and a girl was saying the manager who does the scheduling had a fit one day basically because people are always asking off and brought down the original schedule one day..as if that was her way of saying she was mad..or something. She never said a word to any of us about being mad or like "hey we really dont want you to switch so its going back to the way it was." Not a word. I didn't work with the girl who was taking my shift at all this week after it was approved and I had no way of contacting her so I was kinda trusting that she would probably still show up but who knows, maybe somebody told her not to and to go back to the original schedule. It was all pretty up in the air. So I woke up friday feeling really nervous about it and decided to call and tell them what happened. Instead of trying to understand it the store manager got mad at me and said "Well if she doesn't show up it's going to be written up on your record as a no show." Totally making me feel like I was bailing out on them or making excuses, as if I had made the entire story up. I have been there for 10 months and they should really know me better than that. Yes, most of the people I work with act like that all the time but I don't! I have never once called in and made an excuse not to come, never once not shown up, never once been late for no good reason. In fact I have only been late maybe twice and once because my car died. So it really upset me and irritated me. I hung up with him and then called back after I finished crying to see if I could get jessicas number from the customer service girls and they told me it was taken care of, that they had called her. So I'm pretty sure she ended up coming anyway but geez. Totally stressed me out. Especially since I am in the middle of trying to get this job at Arizona Tile. Really don't want to get in some huge fight or ruin my reference with them over one confusing, unnecessary incident because they don't know how to communicate like adults intstead of children.