yes, the level of doc determines the no of weeks the player is gonna be out.but with level 2 doc and the number of injuries your team is facing,you might be short of players,with many getting injured for more than a game.
It's a different player every time, not the same player
hmmm..but do list the names of players who have been injured and follow their injuries over a course of a season or two and if someone is getting injured more frequently then you should consider changing him.