Whether this movie is worth watching?

IMO no. It's quite a bore actually. The characters are uninteresting which makes it hard to root for them and there is little to no suspense. The story is predictable, which is fine for this type of film, but without any tension or suspense, it's not entertaining.

I mean it's better than some Adam Sandler movies.

No. It's bait and switch. You start out thinking it's a character-driver psychological horror but it ends up being a Friday the 13th/Halloween mashup.

it was better than i expected. more of a thriller, only the final 10 minutes or so become a bit horror'ish.

nope.