To dream of playing the lottery suggests that you are relying too much on fate instead of taking responsibility for your own actions or decisions. You need to reconsider some issue or situation before committing to it.
To dream that you win the lottery represents your inner desires to live without having to worry about financial and material troubles. Alternatively, the dream may be a metaphor that your number has come up and thus imply trouble coming your way.
I had a dream I won the lottery. I was excited because I thought it was the big bucks, but when I looked it up, it was only $60k.
But I was still happy because it was $60k more than what I had before!
What a great dream, and then I woke up.