Is It Normal To Have 40-day Menstrual Cycles Postpartum While Taking Lactare Tablets For Low Milk Supply?

Hi, My baby is 11 months old and due to low milk supply I m taking lactare tablets since when he was 3 months old. I got my period around 4 months postpartum. I had regular periods before pregnancy but now my periods are 40 days apart. Is there any cause of concern? I m worried a lot. Please help