It looks really cool and the music fits the ambient. What I didn't understand was: Why can't I grab any more of those small crystals after the first one?
The crystals are used to refresh your dash, so if you are already able to dash, that's probably why you can't pick up another one. You can store up to two dashes, as denoted by the color of the player. You refresh your dashes by touching the ground and collecting the diamond-shaped crystals. Hope this helps!