Had first postpartum period last month…this month I’m 2 days late

Pre pregnancy I was always right on schedule… baby sleeps through night and I pump 2-3 a day mostly now 2 and also supplement with formula and he eats purées. I was doing 4 times a day and supplementing what I wasn’t making. When my period returned last month I knew it was a matter of time as I had just recently dropped # of pumps. Now it’s 2 days late. Is this a cause for concern? Do I have an imbalance in my hormones? I want to try to become pregnant soon, and last month I really thought I’d start to have regular monthly periods. 2 days ago when it was supposed to come I felt crampy and tired…? Help? Thanks