just worked my first shift

I just finished my first shift w/o a preceptor (although one was suppose to be along for it), i am ready to quit and say see you later. I had several patients were i felt like i didn't do a good job with. I can't use my nursing jugdment to tell a mother that motrin and benadryl are an ok mix for her child? and i can't assume a bark like cough is croup? and what about the baby who might have a broken wrist? ................................questions questions questions.........................i don't want to lose my license but i feel like this might not be the specialty for me. I have a huge problem with not being able to see the patient and most of the time i cannot talk to them. How am i protected? Our calls are recorded, but i can't help feeling if something went wrong the company who i am with as a contract nurse would throw me under the bus. My husband and I have been apprehensive about the position and after my first shift, i want to say no thanks. Should i go ahead and quit or wait til i find another job or what? This is a scary specialty, just has such malpractice overtones..........................All advise appreciated.