As Neils Bohr showed, it is possible for electrons to move between energy levels. Light contains energy. If a photon of light strikes an atom, it is possible for the energy in the light ray to be transferred to one of the low energy electrons moving around the atomic center.
Spotting before a period is due â reasons for spotting before a period can be implantation, from a cyst or a short luteal phase and impaired egg quality. Spotting in between cycles â this is a difficult term to answer but often means your cycles are growing shorter; often with perimenopause.
A lighter period than normal can be caused by many things, including pregnancy, stress, illness, and other things. Sometimes a woman will have spotting and think her period is about to start and not see any more bleeding. This can be implantation bleeding, which is the earliest sign of pregnancy, that is sometimes mistaken for a menstrual cycle. It can also be that your period simply is lighter that month.