There are two basic types of spiritual awakening. I call them fast and slow.
A slow awakening is a gradual build up of ‘pressure’ until the kettle starts letting off steam. Spiritual techniques like chakra opening encourage the trance state that builds up the pressure. Your senses and awareness are heightened and the mind steadily starts to acclimate more and more to the trance state one needs, shifting outside of the time spent meditating and into mundane existence.
Conscious awareness slowly starts teetering back and forth between the two states, mundane and spiritual. Awakening happens when the mundane disappears for awhile and you’re in a spiritual state constantly.
The slower the buildup, the longer the run up, the more ‘complete’ the awakening. Typically after the awakening, several more experiences happen, these we call satori. Depending on many factors, the period between awakening and crash can last weeks to months. The crash can be big or small.
If it’s a small crash, then usually within a day or so spiritual experience resumes. A bigger crash is called a Dark Night and can grind spiritual motivation and exploration down to a complete halt. It takes ego and motivation to pursue a spiritual path, and a crash / Dark Night strips those away.
The removal of ego is the ultimate object of spiritual effort. It’s the ego that wants the experiences, but the ego is also a block to those experiences. When the crash happens and the ego is broken, the broken ego blocks the experiences even more completely. One cannot even motivate oneself to meditate, and the ego keeps the state and perceptions from happening naturally.
A kundalini awakening is the other type of spiritual awakening, the fast type. In this type of awakening, the highs and lows happen at the same time, in a rapid cycle. The onset is sudden, and the relief is similarly sudden. After relief, new spiritual perception may stick around for awhile, unlike with the slow buildups.
I have less experience with the fast-type awakenings, which are strong enough to provoke physiological ‘symptoms’, but I’ve heard tell of them happening randomly at Vipassana retreats, which can be quite dangerous should you attend one before your mind is acclimated to meditative experience, particularly in America where the conductors of the retreats aren’t properly trained.
A fast type awakening can happen to anyone, anytime, anything can trigger them, mundane or spiritual. It’s certainly possible to trigger one as a result of repeated meditations like chakra opening, but more likely you’ll get a slow-type awakening as described above. People new to meditative practice will naturally misuse terminology and so you’ll see a lot of slow-type awakenings called “kundalini awakening.”