Estrogen and testosterone drop for half the week, then estrogen rises again; progesterone rises throughout: People who got used to making you laugh for the past two weeks are going to worry they broke their funny streak when they’re around you. The reason? During Week 1 and Week 2, you were all guffaws as estrogen rose since this hormone triggers a surge of brain chemicals that make you upbeat and more likely to laugh. But, in Week 3, not only does estrogen dip to a lower level, making the giggles farther and fewer between, rising progesterone is also on the scene, making you seem more serious and sedate. Find out more by downloading the Hormone Horoscope App.