There is this young 18yr old lad who worked with me and is my bosses son we get on very well together and one day a work colleague said ''look you two obviously like each other so why don't you go out with each other?'' to which he walked away and didn't come in for the next 2 days.

That means nothing, he probably didn't need to come in those 2 days.  Or maybe he was embarrassed, or didn't know what you thought.

I also heard that he staring at me at my brothers birthday party to which he denied. I get signals from him when we speak to each other and once he saw me waiting in the corridor at work and stood beside me

All those signals indicate he likes you.

(while i was ignoring him) and he asked me what i was doing tonight? to which i replied ''you know'' and he replied ''burton albion'' even though i had told him that the previous day - I think that he possibly had something else to say but chickened out of it?

Yes, I think maybe he did.  And at 18, I'm not surprised he maybe isn't brave to ask someone out yet, or have the experience to know how to ask someone out.

So does he fancy me ?

Sounds like it, but I can't say for sure.  I would say you gave me a fair amount of proof, but not quite conclusive proof.