After exercise, when I concentrated on my heart I used to feel my hands becoming warm, but that was the only response I ever got from meditation and it did not last long. But I recently tried kapalbhati and felt a sort of very light current in head. I tried focusing on that and increased in many sessions of kapalbhati. Now current has spread around my both hands, chest and head, and it lingers for hours, I know kapalbhati is hatha yoga, but is this some sort of explaination for this current? and advice me any buddhist practice to proceed from here P.s. I also feel my face, hands and chest lightly vibrating. This finger and phone shaking even as I type right now.
kapalbhati and hatha yoga have nothing to do with buddhism so ask the same question here https://hinduism.stackexchange.com/ or on reddit
People who talk about vibrations are people who do ''insight practice'' and they say their unpleasant vibrations disappear once they stop their ''insight practice'', so stop practicing whatever you have been doing.
electrical feeling current, hydraulic sensations, vibration, are a universal part of meditation phenomena whether you're practicing buddhist, hindu, christian mystic meditation.
In the suttas, for example, the Buddha talks about it here in SN 54.7: http://lucid24.org/sn/sn54/index.html
and here in MN 62 http://lucid24.org/mn/mn062/index.html
(in more abstract terms of fire and wind element)
All of these phenomena are a natural part of relaxation, pacification (passaddhi) awakening factor. It's described in hundreds of suttas as part of the 7 awakening factors: http://lucid24.org/sted/7sb/allref/index.html
If your energy channels are blocked, then you get vibrations that hurt, are un comfortable, make your body shake as described in SN 54.7. But if you persist in your meditation assiduously every day, then the energy channels will open up and the currents of energy that loop around the body will smooth out, and you'll experience piti and sukha (rapture and pleasure).
Here's the big secret about the underlying principle of how this all works that the suttas don't explain. If you want to advance beyond first jhana, you'll need to maintain celibacy purely (no sex, no masturbation, no lustful thoughts period), and charge up your jhana battery through noble silence (second jhana quality of samadhi, stopping the thinking mind).
Just like if you want to get rich, you have to make money and not spend more money than you make. If you talk and think a lot, you'll be draining your jhana battery, it will never charge up. If you're having sexual activity, it drains the jhana battery much faster and harder. So lay people who have lots of sexual activity, will never realistically get better than low quality first jhana. If they meditate a lot and have a lot of sex, what is the most likely result is the meditation will have lots of shaking, vibration, pain, and disturbing emotions, psychosis.