thing is when i meditate first thing i experience is when i am calm and close eyes i notice some colors floating around me such as purple,red and white and sometime it feel like i suddenly got shot i.e travelling into white light what is it??
also sometime when i finish meditating i feel electrical sensations on some body part like those part are getting shocked or something buzzing under its skin what is it??
Since I do not have these experiences myself I can only guide you with some thoughts I have heard from my teacher, Swami Kriyananda. What you are describing seems to me to be spurts of Kundalini energy rising from the base of your spine (the coccyx center or Muladhara Chakra). There are six centers in the spine that act as transformers, so to speak, for the main energy of Kundalini that travels upward to the brain or to the Spiritual Eye, the center at the point between the eyebrows.
Swamiji continues to say that Kundalini, the serpent power, is man’s greatest single key to enlightenment. Only from arousing this force from its sleep state at the base of the spine from its resistance to divine truth can the soul hope to reunite itself with the spirit.
There is much written about Kunalini and the chakras. You can read Swami Kriyananda’s words in The Art and Science of Raja Yoga and Chakras for Starters books published in India by Ananda. The meditation technique that Yogananda has given us is called, Kriya. This technique gently helps to raise the Kundalini energy. Raising this power too quickly and strongly can be harmful.
Possibly you are experiencing these spurts of energy from the Kundalini. What you want to experience, however, is the full flow which can come with proper meditation techniques, such as Kriya. You can become engrossed in the spurts (the beautiful colors, etc.), but they will not take you to your goal. It is best when in meditation, in the calm state, when feeling this energy, to focus your attention at the Spiritual Eye, the Ajna Chakra. Feel that the energy is going there. Keep your concentration strong at this center. Eventually these spurts will calm down and will flow naturally upward.
Joy to you, Seva