Feeling out of sorts

If you're 'feeling out of sorts,' it means that you're not quite feeling like yourself. You feel a little off, and perhaps a little sad.

Example:
-How are you feeling today?
-Well, I'm a little out of sorts. I'm not sure what's bothering me.

Wrap your mind around

When you're trying to 'wrap your mind around' something, it means you're trying to make sense of something that is really sad, unexpected or shocking that takes you by surprise and doesn't make sense.

Example:
-I can't believe Kyle was killed in a freak car accident.
-I know. I just can't wrap my mind around it. So tragic.