pain in big toe

For the past 3 weeks i've had pain in my big toe and nail for no apparent reason,its very tender even if my bed cover brushes over it it hurts it feels almost like something very heavy has been dropped on it but this isnt the case.i know its not ingrown as i've had that many times and the pain is different.to look at there is no redness or anything although my cuticle seems to have dissapeared and is no longer touching the toe.
any one else had anything like this or any idea what could be the cause?
thanks