Is it bad if you see things in your head that come true within the month?

The question depends on what is meant by seeing things "in your head." If you are awake and seeing things that are not really there, these are hallucinations or delusions, and you need to seek medical treatment. If you are seeing things in dreams while sleeping, that is entirely normal. However, a month is a long period of time in which to assume that a dream has "come true." It is very easy to mistake a feeling of deja vu or a vague recollection of something from a dream, and leap to the false conclusion that a dream has come true. The only reliable means of confirming that any dream has foreseen the future is to keep a written journal of your dreams, dating each dream as it occurs. This will provide solid evidence if and when a dream comes true.