I've been learning German at School for 6 years and still I can hardly remember a dozen of words, but with English it was a completely different matter - I picked it up fairly quickly and in a matter of 6 months I could already speak and understand 80% of what I heard.
In two years my level was 'upper intermediate'.
But I have to say that much of my English experience came from many 'user's manuals', etc I had to plow through to learn Basic, Pascal, C/C++, etc
There was no localized software in my time - everything was in English back then. I learned what this or that command do by trial and error ))).