Karla is right but i will add that you could also use a different conjugation of the verb 'to dream' and say 'Last night i dreamt of you.'

It helps me a lot! Thanks!! ^^

To dream of is used when you are talking about what you want or desire. I dream of being a ballerina when I grow up. To dream about is used to talk about the subject, for example I dream about dragons sometimes. I dreamed about eating sushi in a fast food restaurant. (Used in past) Hope this is helpful