vagh tup neH ret vIghro' vIlegh 

Is this correct, and if yes what would it mean ?

only five minutes ago, I saw the cat ?

or

just five minutes ago, I saw the cat ?

or 

both ?

I would point out that I saw the cat is a perfective concept. <timestamp> vIghro' vIleghpu'.

You would only say just <timestamp> vIghro' vIlegh if you were saying something like five minutes ago I was looking at the cat when suddenly...

-- 
SuStel
http://trimboli.name