You may wish to further your Reiki by receiving Kundalini Attunements and opening up yourself to those energy fields known as Kundalini. Much like Usui Reiki it is given in three attunements. There is no formal pre-requisite to receiving Kundalini Reiki, although I believe it is best to be attuned to Reiki 1 to understand the full force of Kundalini.
Someone who has had a tough time with Kundalini awakening can most benefit from Kundalini Reiki. Becoming attuned to Kundalini Reiki means that over a period of time you will go through a complete cleansing of the Chakras. Just as in the modern day medical symbol of the two snakes climbing up a pole the snakes represent the Kundalini rising within us. That is where they got that symbol from.
Kundalini is opening yourself up to the earths energies. Just like Usui Reiki, Kundalini Reiki means certain Chakras/ healing channels are opened up in you. Kundalini is also known as "Kundalini Fire" because after ones attunement through Kundalini the energy runs all the way up through the body through the "main energy channel" and out the crown Chakra.