Yes, QUICKS is a Scrabble word!

Letter values in Scrabble US: Q 10, U 1, I 1, C 3, K 5, S 1.

Is it a valid word?

QUICKS is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

any area of the body that is highly sensitive to pain (as the flesh underneath the skin or a fingernail or toenail)