"The future isn't going anywhere and it will still be there tomorrow" is a good way to calm down and think. But if you keep thinking that then before too long your future will start getting narrower and narrower as opportunities are missed. See what I mean? Scary.
It's okay to be scared of that. The backbone of the attitude of allowing myself to tell myself that the future will be there tomorrow is that I trust myself not to let the future narrow. I have to trust in my own self to know that I have more time than I think I have. I tell myself the future will be there tomorrow because I need to get through today in order for tomorrow to even exist. At the same time, I trust myself to make things happen later on. I know I can work hard, and I know that I've never had a problem getting a job. I also know that I spend too much time being scared of the future, so much that I'm already missing out a lot on the life that I'm living right now. And in a way, I'm more scared of letting my life pass me by while I'm still living it. Today is already here, so why am I scared of not living in the future when I'm living already right now?
The future will be there tomorrow. It's far more important not to forget about today because when you stop looking at each day you live today, that's actually how your life ends up passing you by. The collective of the days you lost being scared of the future ends up comprising all the days you regret not living later on.
In other words, have some sort of outline for the future that you will get to in the future. Other than that, there's a part that really has to let go of those dreams and aspirations and desires, and learn to be happy in the now. If you can't be happy now, how can you believe you will be happy later?
If I can't enjoy the boy toy I have while I have him now, then I can't expect to enjoy him some other time later. If I can't enjoy the process of working towards being a broadcast engineer, I highly risk not enjoying being a broadcast engineer at all. The process is where I learn the things I should end up loving to do as a career. Thus, if I find I'm not enjoying the process then I can change it while it is still now.
The future will be there tomorrow, and (as Dovahkin would say in ES:Skyrim) the future will have to worry about itself. Your future self will have to worry about itself. It's okay to be scared sometimes. But it's not okay to stand still. The now is happening right now, and if you're really scared of not enjoying life, then there's really no better time to get to it then right now.
The real problem is that few people know what they actually enjoy doing. so I guess we all have a lot of work to do on getting to know ourselves and what makes us happy.