Multiple period months

Stephanie • Trying for one together. I have one of my own, she is 8. I have 2 step kiddos 16yr old son, 13 yr old daughter and 5 pit bull furr babies
I have anywhere between 2 or 3 heavy periods a month that last 3 to 4 days each. I input them on glow but now i have multiple ovulation weeks also. How do i know which is correct?