Twitching????

Kala ♑️ • 18. Capricorn sun, Aquarius moon, Taurus rising. Tarot card girl. Avoiding pregnancy. College freshman.
I keep feeling this little bump bump on my right side right above where my underwear hit. Earlier it got so strong I could see my skin pulsing a little. What the hell is happening to me right now im on day 4 of my period and I was late by almost 5 days. Should I be concerned?