i always have bad dreams they either involve animals such as cats, dogs, rats, snakes attacking me or being on me and not getting off or dreams of people i know dying. most of the time my dreams are not pleasant. just 2 nights ago i had a dream of a black dog attacking me, does this mean anything? should i pay sadaqah? if so how do i pay it?

You should recite 4 Qul, Ayatul Kursi and Tasbeeh of Zahra (as) before sleeping.

Also sadaqah is giving any amount of money or goods to a person in need. No specific amount.