Probably not, particularly if you practice yoga intermittently or concentrate only on doing the asana. Few people report actually feeling the prana flow up their spine.
Perhaps you suddenly feel balanced. Your body is more supple and your mind calmer. A sense of comfort and confidence prevails. Even without more sleep, you have more energy.
Little things that typically bother you suddenly appear insignificant. Your intangible energy force, or prana, is percolating.