Pre-travel depression

Post-travel depression does exist. I went through its lighter versions a couple of times myself, as this won’t be the first time for me to travel. I witnessed its more severe versions when supporting friends who just returned from longer backpacking trips and fought to get back to “normal”.
But does pre-travel depression exist? Is it okay to feel bad, while I know that I’m going to travel for months and most probably amazing experiences are awaiting me? May I be sad and feel low before I start my trip?

I feel ripped apart. Major part of my energies and my thoughts is focused on the future, on the travel. I run up and down for my new IDs, the visa, vaccination, register my webpage and book plane tickets to destinations that I do not even dare to say out loud as they feel so unreal. But I don’t know how to share this excitement with others without showing off. Sometimes it feels lonely. My friends live their nine-to-five lives and are not always available, when I’d need them. And in these moments I realize, that it will be like this for 5 months. I travel, get to know a lot of people, maybe even make friends and will have amazing adventures, but I will be alone. I travel alone.