I'm 28 Years Old, Have A History Of CHF(one Incident

I'm 28 years old, have a history of CHF(one incident requiring hospitalization). I became preeclamptic in my last trimester, was induced/resulted in a cesarean with live birth at 37 weeks. My son is now three months old and I still haven't had a period, and I'm beginning to experience edema in my feet/ankles. It's mild and not painful, not like when I was in heart failure. Height 5'7, Weight 280lbs.