Extreme menstrual groin pain?

Have any other women experienced a completely unbearable ache in their groin while fasting? From hours 50-68 (day 3) it kept me from sleeping, and I was an absolute wreck the next day. Fever, headache, menstrual groin pain, weakness, shortness of breath. It was like the sickest I've ever been! I know day 3 is often the hardest, and maybe it was a coincidence that getting my period 2 weeks late during this fast was the only reason I had so much trouble. I had to break my fast with broth and a boiled egg so I could take some Advil. The relief was worth it. Do you think it was a pathogen die-off combined with one the gnarliest periods of my life? I thought fasting while menstruating was generally a good idea... but maybe not when it finally comes after being late for 2 weeks?