The descent of calm and light which you experience is a sign that the sadhana has actually begun in you; it shows that you are open now consciously to the Divine Force and its workings. The descent of calm and light into the being is the beginning of the foundation of the yoga. At first it may be felt in the mind and upper part only, but afterwards goes further down until it touches all the centres and is experienced in the whole body. At first it comes only for a moment or two; afterwards it lasts for longer periods.
The other experiences show that the faculty of inner vision is opening; this is also a part of the yoga. The fire seen by you must have been the fire of aspiration lit in the vital being. The other things you saw are not definite enough to be interpreted.
Continue your progress.
Our blessings and protection are always with you.
Ref : Words of The Mother Vol. II