67 views and no replies... I'll try to help you out.
I've actually felt like this before too. Wondering if the ratio of slow-twitch vs fast-twitch muscle fibers has something to do with not attaining super-human WFD type of speed. I also race mountain bike endurance events so it's safe to assume I have more slow-twitch than fast-twitch muscle fibers... But back to drums, it's just a matter of consistently working at getting comfortable at a certain tempo and slowly increasing from there...even if it's 1 or 2 bpm at a time.
There are tons of topics on here regarding 'hand speed', 'fast singles', etc. It may help to do a search...
Why do you think you are so slow anyway? How fast can you play clean singles (in 16ths)? If it's like 50, then yeah, maybe you are slow.
But everyone starts somewhere, so start practicing single strokes (in front of a mirror helps me), watch your stick height-keeping them the same. Wherever your form falls apart, back it down a little and work there. Eventually, you will build muscle memory which will help you feel more comfortable. Then work on increasing tempo slowly and consistently (as possible).
Hope this helps. Just keep plugging away. In time you will notice an increase in speed and fluidity.