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.
More than half of women who menstruate report some pain from period cramps for a day or two each month, according to the American Congress of Obstetricians and Gynecologists. While menstrual cramps, also called dysmenorrhea, are usually not a sign of a serious health condition, they can put a crimp in your lifestyle.