"The prophet that hath a dream, let him tell a dream; and he that hath my word, let him speak my word faithfully. What is the chaff to the wheat? saith the Lord." (Jeremiah 23:28)
I can't tell you how many times I've awakened from an intense and odd dream, full of seeming significance and allusion, and wondered just what it meant. Nothing. That's what. I'll even write it down and revisit it later and stand in astonishment at its irrationality. Contrast that with the scores of dreams I've been blessed with that weave together a narrative of an overarching thing that God is showing me at a particular time or season of life. It goes without saying that I believe God speaks through dreams. Earlier on in the chapter, God speaks out against false prophets and their "dreams and visions". They were, He says, "prophets of the deceit of their own heart" (from verse 26). It's more than a little discomfiting to realize that there are all sorts of ethereal ideas that come across the screens of our minds and hearts that mean nothing. God, in the heading verse, heartily encourages the open discussion of ideas so as to see His word—His truth—rise to the surface. The idea behind wheat and chaff comes from an ancient farming technique where one would take handfuls of harvested wheat (or whatever) and throw them up and let the wind separate the husks, or chaff, from the actual kernels of wheat. It's a fitting metaphor used several times throughout the Bible and still in practice today.
Fast-forwarding to the days of the early church, Paul expresses a similar idea in his first letter to the Christians at Corinth. "How is it then, brethren? when ye come together, every one of you hath a psalm, hath a doctrine, hath a tongue, hath a revelation, hath an interpretation. Let all things be done unto edifying." (1 Corinthians 14:26, emphasis mine)
Whereas the chapter from Jeremiah pertains to a specific point in Israel's history, where the lies of false prophecy (as transmitted through spiritual dreams and visions) were endemic so as to incur judgment, the atmosphere of the early Christian church is a little more low-key. But no less important. The wide-spreadedness of early Christendom had not reached the national level when Paul wrote his letter and so keeping a lid on the lies that try to spread alongside a spiritual revival was done in this way. Paul doesn't doubt that "every one of you hath" something. Everyone, it would seem, was seeking God to a lesser-or-greater extent. And God was providing answers and insight. But the real key to the power of what was cropping up in the minds and hearts of those Christians—to where they'd be able to "mass-produce" it—was its basis in the Word. That's what tells.
I wholeheartedly encourage the dreamer, whether literal or figurative, to record the things that make them think. Whether it's an idea, or a dream (or nightmare), or a piece of wisdom explained just-so. Write it down and share it with the Holy Spirit. He's the one who has the ultimate handle on what goes on in the spiritual realm. A realm in which we are all active participants.
The writer of Hebrews chides his readers for their lack of understanding in spiritual matters: "For when for the time ye ought to be teachers, ye have need that one teach you again which be the first principles of the oracles of God; and are become such as have need of milk, and not strong meat. For every one that useth milk is unskillful in the word of righteousness: for he is a babe. But strong meat belongeth to them that are of full age, even those who by reason of use have their senses exercised to discern both good and evil." (Hebrews 5:12-14, emphasis mine)
That last part is what gets me. What they're saying is when we meditate and think about and use God's Word, our senses, our ability to know what is lie and what is truth, will develop. This doesn't mean we leave off interacting with the Holy Spirit. But coupled with Him, God's word is the essential guidebook for our wanderings through dream country.