你今天看上去很伤心。 You look sad today.
你今天好像不高兴。You dont look very happy today.
你看起来很疲惫。You look exhausted.
你该放松放松了。You should take it easy.
你今天有点儿不大对劲。Something is wrong with you today.
放松点儿。Kick back!
别急。There's no need to rush.