Getting the Experience I Need

Finally, I am getting some much needed experience. I have been working at the attorneys office more and more lately. I have been filling in for the other secretary from time to time whenever she cannot make it to work. I’m not used to being at the office more than one day a week. I start to panic when the phone rings off the hook, when clients come in, and when I am doing my own work. How do I keep my anxiety to a minimum? I want to do a good job and I don’t want to mess anything up, especially legal papers?
I have worked for the attorneys going on six months now. I would like to use the attorneys for references for potential jobs in the future. Is it too soon to ask them to be a reference for me? I try to keep in communication with them by asking questions whenever I don’t understand something, but sometimes I feel as if I am a “slow learner” and I’m not picking up on things as fast as I should. But I do feel that since I am usually only at the office one day a week (except in special circumstances like the present) I am doing well. (At least I hope so!)