Will you have some introduction classes that day?
e.g. I remember that at my university there were some special things in the first days for foreigners, just to help them with the necessary things.
And everyone survives
. Don't worry, other people have dealt with it, and other people were less smart and probably also less prepared than you. -> you can do it.
I have a ton to do before I even leave. I have to make packing list, get adapters and ethernet cable, call insurance company, get extra meds for five months, visit dentist, visit doctor, clean great-aunt's house, pack everything, discuss phone situation, find various paperwork, get ISIC card at school, activate new debit card, put a ton of money in it, since I'll need hundreds on the first day, come up with a thorough travel plan, and probably some other stuff.
I'll have a ton of flying to do. Two hours to DC, eight hours to Zürich, and one hour to Köln. Plus at least two hours of layovers. I'll be in planes or airports from 1:00PM Monday to 10:00 AM Tuesday.
When I land in Köln, exhausted from sleep deprivation and jetlag and alone in a foreign country, I'll have to ride a bus to Bonn, ride a shuttle to the International Office, provide proof of health insurance, locate nearby English-speaking doctors, sign a lease, pay three months' worth of rent, possibly open a bank account, register with the city, pay 255 for various stuff, get a residence permit, get moved in, and probably do a few more things before I drop dead.