Calm down. The expectations of incoming interns are very low. Have a very low threshold for calling your senior resident/attending if you have any questions. It is much better to be conservative at this point. Carry your ACLS card in your back pocket to remind you of the algorithm.
Here's what will happen:
6pm (or whatever time): show, up, get sign out about the folks you're caring for overnight.
6:01 ER will have some 80 year old woman who "just doesnt look right" or is "feeling a little weak". You will admit said octogenarian. This will be the first of 750 such admissions you will have this year. This will entail seeing the pt in the ER, calling your attending/senior, putting in the admit orders ( your senior can help you with this), and then repeating this process several more times overnight.
7pm: nursing shift change.
730: nurses start looking at charts. They start calling you about ambiguous orders from 6 hours before. If it's critical to fix overnight, then fix it.
8pm: Nurses would like things to quiet down, so they will call you asking for ambien, benadryl, trazodone, or zyprexa for their patients. Recognize that most people don't go to bed at 8 pm, and will have a hard time sleeping with the lights on, and the TV blaring. Get the pt a good sleeping environment, and dispense sleepers VERY judiciously.
9pm: ER will have 2 more patients for you.
1030: The obese COPDer will refuse his CPAP and will desat all night long.
2am: Recently graduated RN will be reviewing the I/O's and notice that the pt in bed 507 hasn't had a bowel movement. Remind her that unless they are being prepped for a colonoscopy overnight, most people don't poop at 2am. Be very nice.
1200- 6am: people will have actual issues requiring intervention. Know how to contact the rapid response team for an acutely decompensating patient. CALL YOUR SENIOR.
4am: labs will come back and people will page you about abnormalities. Ask your senior how to replete electrolytes (since somehow they never taught us the specifics of this in medical school).
6am: sign back out the various things that you did overnight.
620: your first night of call as an intern is over, hopefully everyone that was alive when you came in is still alive.
Things that will help: Keep a list of all the patients you have to care for and any time you are called or do anything to/for them, write down what you did and what time it was. IF you can, also have available the reason for admission, any relevant pmHx, allergies, CODE STATUS, and current rx.
Good luck. We all got through it, you can too. ASK FOR HELP if you don't know. It is better to look foolish and ask questions than to save face and risk hurting someone.