Rough night

Yesterday was a rough night. Not sure what happened coz she was great for so many nights. Yesterday, she wouldn't settle to bed and needed a full hour and a half of coaxing. I was having a headache through all that time, and only dared take medicine after she slept after feeding. Then she woke at her usual 2.30am but wouldn't sleep til 4am (that worsened my headache), only to wake at 5+am! Normally she slept well after feed. Was it my supply lessned? I had to question my supply because normally i would feel quite engorged at nights, but not last night. Could it be the medicine?