Rocking is associated with shifting energy, usually for a positive change so enjoy it.

A couple of week ago at a group meditation I was doing just that, and positive changes started to happen.

It doesn't really matter if you have had entire life of training in meditation to what you experience, as it depends on your spirit guides and you and your life's path follow what you feel and experience. :yes:

Occasionally in meditations, a person may experience twitching of muscles, jerking of the body, or energy releases, which feel like little lightning bolts. Don't be bothered by this. It's just a sign that your meditation has relaxed you enough so that body tensions are being released. Energy will flow better afterwards.
Sometimes in meditations, a level of relaxation is so deep that tensions in muscles will release, thus bringing to consciousness memories of past experiences or attitudes. Observe them and let them play out their scenes. They may have been locked in the muscles system for years or for centuries (past-life influences). This is a form of cleansing blocked energies.

Novice Meditator