Congrats! ^^
There are a total of 3 different enemies in the game. To find out what they are, you'll have to climb higher ;) (or just check the other comments)
The game technically has no end, so an indicator did not cross my mind, but that would be an interesting idea. I had so many ideas of effects for that speed boost but deadline o'clock came too soon and that was all I could get in. Guess I'll just keep these ideas for next time.