Symptoms of insect bites and stings. An insect bite or sting often causes a small lump to develop, which is usually very itchy. A small hole, or the sting itself, may also be visible. The lump may have an inflamed (red and swollen) area around it that may be filled with fluid. This is called a weal.
Hormones and the Brain. That's not to say estrogen isn't a major player in regulating moods. Estrogen acts everywhere in the body, including the parts of the brain that control emotion. Some of estrogen's effects include: 1  Increasing serotonin, and the number of serotonin receptors in the brain.
These temporary moods swings, like the those brought on by menopause, are caused by physical and hormonal changes in the body. During menopause, the body decreases its production of estrogen, which directly affects serotonin levels. Serotonin regulates mood, and an imbalance in it can cause mood swings.