You poor soul!
A bhrònag!
Let’s have a look at a very basic conversation:

Madainn mhath, Iain.
Good morning, John.

Latha math, Anna. Ciamar a tha sibh?
Good day, Anne. How are you?

Tha mi tinn. Tha mi sgìth.
I am sick. I am tired.

Dè tha ceàrr oirbh?
What’s wrong with you?

Tha an cnatan orm.
I have the cold.

Is bochd sin, a thruaghag!
That’s a shame, you poor soul!