The general solutions for the harmonic oscillator differential equation fall into four general categories: 1) Undamped: [math]x(t) = Ae^{i\omega t}[/math] This is a free-running sinusoidal oscillation that doesn't change over time.
Key Facts. 1  Itâs normal to have mild cramps during your period. 2  Menstrual cramps often start 1-2 days after your period begins. 3  If your cramps donât get better with over-the-counter medicine, you should see your health care provider.
Some pain, cramping, and discomfort during menstrual periods is normal. However, excessive pain that causes you to regularly miss work or school is not. The medical term for painful menstruation is dysmenorrhea. Primary dysmenorrhea occurs in women who experience pain just before and during menstruation, but who are otherwise healthy.