Harness your anxiety by putting it to use: pack extra bottles of water for the trip, take a little extra cash, more than you had planned; pack an emergency bag with items you might need like candy bars, a blanket, flashlight, extra batteries, cookies, bandaids, a hat, a couple paperback books to read, etc. Make a list and check it twice. Leave your address and phone number with two friends, make a plan to call them when you arrive in Germany, or a designated time. Then, have a cup of camomile tea and get some sleep.