Bad headaches postpartum

I'm 3 weeks postpartum and have been getting headaches since day 2. I told the nurse in pp I had a bad one and she wasn't concerned. I take ibuprofen and Tylenol but it doesn't help enough. Someone suggested caffeine but can't do that because my heart is too sensitive to stimulants. I did get an epidural but not sure if a spinal headache would last this long and my headaches aren't severe migraines. I assume it's just hormones, lack of sleep, or something simple but I'll call my OB tomorrow anyway. Anyone else experience headaches for this long postpartum?