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.
Cramping may be a symptom that ovulation is taking place. Sometimes the menstrual cycle is delayed, and instead of menstruation, ovulation is still taking place, giving rise to cramps but no period. The period follows two weeks after ovulation, and this may be accompanied by other symptoms like constipation and gas. Some women have irregular menstrual cycles, which mean that their ovulation and period may be early, late, or even nonexistent in a given month. Some women therefore miscalculate the expected date of their menstruation, leading to worry when experiencing cramps but no period.