CathInfo.com

To start, you need to sleep consistently every night. This is extremely important for your physical and mental health. If you don't, then it will start to affect everything both short-term and long-term. Don't use any sorts of medications or herbs or electronic knickknacks. Just resolve to set a time every night, before midnight, when it's lights out and screens off, no joke. (Lots of other things can be said about exercise, nutrition, purposeful relaxation, etc., but that's all part of striving toward a well-ordered daily life. Not easy, that's granted.) 

You say you have vivid dreams. When the brain is sleep-deprived, it does REM-rebound to catch up frantically, and this means the dreams can be intense and memorable. That's a signal to you that you need to get at least 6-8 hours, since REM sleep doesn't usually kick in till after about 3-4 hours in normal adult sleep. REM sleep is necessary for a healthy brain and body too. Ignore it, and that risks metabolic and cardiovascular trouble in a few years, not to mention early onset dementia, and in the here and now, lower reactions times, increasing the odds of preventable accidents.

You say you have deja-vu. This happens when there's a glitch in how the brain encodes memory in the part called the hippocampus. In a healthy person with enough sleep and not a high level of stress, this memory storage is accurate enough that we can distinguish immediately between "happening now in front of me" vs. "happened a while ago, not now." But in sleep deprivation and/or lots of stress (whether physical, cognitive, or emotional), the brain sometimes takes in a new experience and the hippocampus sort of short-circuits and encodes it as something that already happened in the past. Combine that with the stress/sleep deprivation of that moment, and the person easily can believe it's an uncanny premonition or message from beyond.

Yes, SOMETIMES it's not about the above, SOMETIMES it's a genuine sign. But that's very RARE, and we should always try to fix the sleep/stress part first. Also, the preternatural powers know to mess with the mind of someone who's under a lot of stress. Instead, focus on taking the necessary steps to fix your daily habits so these troublemakers stay away from you. Ask for help from the Holy Ghost, your Guardian Angel, and our Blessed Mother.