ttc and ovulating

sorry for the long post

been trying for the last 6 years,naturally and been through 2 ivf,since the begin of this year i’m having weird feelings,like when you know it’s gonna happen,had my period on the 15th of feb,been checking my opk daily,using two different apps,one app told me that i had ovulated last week,definitely had the symptoms but then this app told me i would ovulate today,been with cramps and pains for the last 5 hours,then all of the sudden went to toilet to find out some dark brown blood,still in pain,but that for me with my last mc had exactly the same syptoms,nausea,dizziness,cravings,and that’s how i found out i was pregnant(lost the baby girl at 13 weeks😢) now i’m getting exactly the same,probably need some support from you guys and your opinion,TIA