This cheatsheet will give you an overview of the common symptoms for each cycle phase. The symptoms can be physical, psychological or both.

For each symptom, there is a physiological explanation to help you understand better what’s going on.

SymptomCause
Period (~days 0 – 3)
DiarrheaProstaglandins
Low progesterone
Feeling highEndorphins
FatigueDehydration due to loss of blood and diarrhea
Hypoglycemia
Low appetiteInsulin sensitivity
Mild PainUterine contractions
Severe Pain Multiple (could require medical attention)
Follicular (~days 4 – 10)
Improved moodRising estrogen/serotonin
OptimismRising estrogen/serotonin
Energy levels riseRising estrogen/serotonin
Low appetiteInsulin sensitivity
Libido risesRising estrogen
Ovulatory (~days 11 – 14)
High energy levelsHigh estrogen/serotonin + testosterone
SociabilityHigh oxytocin
Social intelligenceHigh oxytocin
Desire to bond with loved onesHigh oxytocin
Great moodHigh estrogen/serotonin + oxytocin + testosterone
CourageHigh testosterone
CompetitivityHigh testosterone
High libidoHigh estrogen + testosterone
CreativityHigh estrogen/serotonin
Moderate appetiteInsulin sensitivity
Anxiety (less common)Bad brain response to high estrogen/serotonin