Yes, DILLS is a Scrabble word!

Letter values in Scrabble US: D 2, I 1, L 1, L 1, S 1.

Is it a valid word?

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

aromatic Old World herb having aromatic threadlike foliage and seeds used as seasoning
aromatic threadlike foliage of the dill plant used as seasoning

Also: anethum graveolens, dill weed.