The Beethoven Variations

So I once tried to do a Theme and Variations based on the A minor section of Rondo Alla Turka, which, that section is already in ternary form, the most common form used in a Theme and Variations. But I didn't get very far with it. So I decided to try doing a Theme and Variations again, but this time with a different composer as the root of it. Specifically, I went with Beethoven and even more specifically the first theme of his fifth symphony. To make it easier on myself, I went for a string quartet arrangement of it, so that is what you will hear and see in the Original Theme part of my Theme and Variations. I also started working on Variation 1, which I decided would be a fugal variation.

Once I get past the exposition of the fugue, which is the first phrase of the theme(that initial unison phrase), I'm not sure what to do to make it fugal but at the same time still have that Beethoven's fifth feel to it. That is probably going to be the hardest variation to compose, this fugal variation. What do you think of it so far?

There's not really enough of the fugue variation to make any judgments... it definitely sounds like a sequence by bass fifth from what's there. 
Saying you want to make it "fugal" means something very specific, and in that language, you've achieved stretto from the very beginning which is a little odd; I would focus on free imitation. It'll achieve the same effect you're going for.