Hello.. Last Month Before My Periods Came I Planned For

Hello..
Last month before my periods came i planned for a baby but after 7 days my period came and it fails 0n 11 june..

My periods is only of two days..
So again I planned for a baby on 15 june...

But it also fails now again my periods started in the month of july yesterday on 9 july...


I didn' t understand the reason where the problem arises

Is there is a wrong date planned for baby i mean kya mene galt date me baby plan kr liyaperiods ke acc.