I think that long/short focal lengths is completely different to fast/slow, which usually refers to apertures and f ratios.
Your focal length is 900mm. I'd say that's at the shorter end of focal lengths if it's in the 600-900mm range. Focal length determines the field of view.
Your aperture is 130mm (not 130cm!
), and dividing this into your focal length is about 7 which is where the f/7 f-ratio comes from. This is a measure of the lens/scope's light gathering capability. The wider the aperture, or hence smaller the f-ratio for the same focal length, the quicker it can gather the same amount of light, which is why they call them "faster".
Considering some Newtonians/reflectors are in the f/4.5-f/5 range (without reducers/flatteners), and some SCT's and Maks etc are in the f/10 range (without barlows etc), I'd say your in the medium fast range?