Very Poor Showing

I am so disgusted with myself it isn't even funny. I am also very ashamed of myself. I went in to work today at 9am. I figured surely I could work a normal shift, I have been doing so well lately. I think the first hour went okay, I say I think because I am not sure, I didn't really notice anything amiss in the first hour anyway. However, it didn't take me long to start noticing some problems. The first thing I noticed was when gas customers were purchasing other things other than their gas, I was ringing in all the purchases on the register okay, but when I would run their credit/debit cards through the machine I was only charging them for the amount showing on the gas console. Considering that I caught that happening on several occassions, I can only imagine how many times it really happened. My cash will be so short tonight, I can only imagine. By now I am also noticing that I am getting very weepy over the littlest things. One customer told me had to have his sheltie put down last week and I cried for about ten minutes over that. Then the cigarette order came in and as per usual I started to put them away and stock the shelf. After I had them about half put away, I suddenly realized that I had NOT been checking them off against the invoice. OH MY GOSH!!! That is a big problem, we now have no way of knowing if we have been shorted on our order, and with the price of cigarettes and with us having been shorted on an almost regualar basis... this is not good news for me. Next I had a customer complain that I was being so slow... oh yeah, I told him fine, go somewhere where he could get faster service and promptly turned to the next customer completely ignoring him. I think I am going to be fired after today.
I love my job and I love this little town, but I find myself wanting to move... to move far away somewhere.