1. This was the worst decision of my life.
What am I getting myself into? Why did I think I could do this? I wish I could go back in time and tell my six month younger self that I am an idiot: these are all thoughts that will run through your mind at some point in time. It may be halfway through your fourteen hour flight, or it could be the first time you walk out of your hotel into the bustling unknown city, but it will happen.
2. I need my mother/boyfriend/dog.
This is the thought that will go through your mind as soon as something doesn't go to plan; planes will be late, hotels will mess up bookings and you will get lost. But while this thought is perfectly normal and 100 percent, completely fine to have, don't dwell on it: tears will get you no-where. Instead, put on a brave face and you give that concierge a piece of you mind (and booking reference number).
3. OMG, look what I just did and I'm still alive.
That first time you conquer something that you would usually rely on someone else for is always an amazing feeling. If it's your first trip alone it could be something as small as navigating the subway system of a foreign city, but nonetheless when you've conquered whatever the challenge may be - and realised that you can indeed do this - you'll have that sudden rush of 'I can do anything'.
4. I am the most awesome/incredible/mature/organised/smart person ever.
Travelling solo can be a huge learning experience. Not only will you learn so much about yourself by being forced to spend time with you and only you, but you'll gain confidence which will filter into every aspect of your life back home.
5. This was the best decision of my life.
As your trip draws to a close and you're about to head off home you'll look back on your travels and realise that the attempt to travel solo was a great decision. While travel buddies are awesome, sometimes the push to really step out of your comfort zone and experience a new world comes when you have no-one else to rely on. You'll also realise all of the fears you had (see 1 and 2) were unfounded; although that probably won't stop you from having them again the next time you set out alone...