Afraid of working.

I don't know why, ever since I got my new tech job, I've been so afraid of going to work. It's such a good job, and I was completely blessed to get it. I mean I get why I am so afriad, I guess I feel like I don't know as much as everyone else, and the day just takes so much out of me. My back kills by the time I get off and all I want to do when I get off is go to bed, and I work 12 hours tonight and tomorrow..then off three days, work two more days, and off for seven days..and somehow I feel so afraid to go into work. I am afraid because if someone codes, or something happens when I am around, that I may do something wrong. Sometimes I feel like I am in way over my head, and I will never fully learn everything. I need a system, like to write everything down about the day, so I can learn better..but I still dread going into work. I love working with the people, I love the other techs and nurses, but somehow I feel so unprepared for this job, and I have noone really to talk to, in housekeeping..it was my family, and yea i disliked the job, but i didn't mind coming into work. I knew what to do, and the worst possible thing that could of happened to me was maybe being in a room where someone codes...but I wouldn't have to know what to do...but now I have to be fully aware of everything. The patients breathing, and what forms on them, I need to know so much...and I feel like I know nothing. I don't know the names of anything, I have to ask the nurses for everything. I can hardly remember something when someone asks me..I guess I am just not as prepared for this job like I thought I would be. There's so much to do, and sometimes I don't even have time to just sit and chill for a minute without someone looking at me like I'm not doing my job. It's so hard and crazy...and now that the only lady that understood me got fired...the one who had as much to complain about as i did...i feel so alone. like everyone else can do this besides me...i don't know what to do besides pray and wait for my 6 months to come..so i can transfer to another floor that is easier. I know that being on the medical floor is hard because you get every type of patient..and we are constantly full...but gese...why is it so hard for me to grasp onto...am i making this more difficult than it really is? Blah... idk....I keep telling myself it's going to get better as time goes on..but i don't know if I fully believe myself. The good thing is..the days go fast ..really fast. So i don't have time to think about how much I don't know..i just ask for help. I need to pray...God can handle this. He can help me.