Please help: Something that I've dreamt about through my entire life

As long as I can remember, I've had this very same dream theme (at least once a year) that I don't like at all. It would be greatly appreciated if someone gave me their thoughts about this because I've asked about this before both here and on other forums and never really got an interpretation. I know there's a lot of ppl who want their everyday dreams interpreted but this is nothing "everyday" so please give me your thoughts and a few minutes of your life and I'll be very thankful.

The theme is very simple, it contains only 2 elements (with various random surroundings) that goes from being one, to many, and the dreams come with varying degrees of fear/despair.
In these dreams, there is railroad tracks in front of me stretching from the right to the left (or other way around) and I have to cross these tracks since there is no way I can go around them. I look to both sides, but see no trains coming. But once I get up on the actual track there is a train comming at extreme speeds, almost running over me (they aim for my death). Sometimes it's just one track, sometimes there are many I have to cross, and sometimes my movement speed decreases severely once I get up on the track(s). I always evade them though, I never die. But I always feel like Im "not gonna make it".

I have no idea what these dreams mean, since it has nothing to do with the "normal" interpretations of trains or railroad track. I think it's a dream related to fear of something, but of what I don't know.
The last time I had a dream like this (which was two days ago), the theme had changed slightly. There was a railroad crossing now (road crossing a railroad) and the safety bars where down. I looked at both sides but saw no train, so I thought about crossing it anyway but for some reason I didn't. So I waited. And after a few seconds I heard a terrible scream from someone else getting run over by the train somewhere.

Here is all the help I can provide.
I think that maybe you are feeling like you want to start a project, or get into something new, or get over something. You consider all the posibilities and all the things that go wrong and you decide to go into it. Your fear is that whilst doing the project you will run into trouble and not be able to get yourself out. You think that this problem will surely be the end of you, but in the end, everything works out ok. I think the number of tracks represents all of the projects you wish to begin at that time.
Perhaps the one the most recent one that you have experienced is you wanting to get into something new, but you know something will go wrong. So you don't, then you watch othesr fail.

This is the best I've got. I hope it helps.

"I'm not gonna make it".

Many dreams record very spoecific emotions... they are in fact very much a diary of the previous day(or thoughts about the day to come). so try to locate ways in which that particular quote was particularly relevant. It may have been an actual situation. It maybe merely some conversation that was taking place insde your own head... but in some way its likely that something down to earth and real triggered this dream.

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In dreams your thoughts are portrayed in a very abstract way using images and feelings. A dream will normally refer to some new feeling or conclusion regarding your life. Dreams then are about ideas and higher intuitional thinking. But there are real problems associated with understanding dreams. A dream will refer to situations in your life which are very complex and really impossible for me or anyone else to imagine. A snake in dreams is a very general theme which can have a million and one real meanings. That symbol has a very real and precise meaning in terms of your recent thinking.
Try these pages as they help you understand the process of dreaming
http://www.unclesirbobby.org.uk/dreamessay.php
http://www.unclesirbobby.org.uk/dreamessayhowto.php
http://www.unclesirbobby.org.uk/dreamessayhowtopost.php
http://www.unclesirbobby.org.uk/dreambookpolice.php

I think landlocked11's reply is very good. But I have a little bit to add from my own similar dream experience and my interpretation of that.

I dream that I am trying to cross the road. There is traffic coming but there should be plenty of time to cross. As I am crossing it's as if I am going in slow motion and sometimes I can barely move at all. Its as if my mind forgets how to walk almost.

For my own dream (which I have had for years and years) I take it to represent the problems I have with finishing tasks and procrastination. You want to much to reach the end but try as you may you never seem to get there. Fear plays an cruicial element in the problem I feel, hence the fear of getting run over in the dream.

You dream of course is different (is a train and it comes out of nowhere) and only you can know where the parallel lies for you, but hopefully this has given you something to think about further. Please let us know if any of this helps.