Is a small amount of dark brown discharge and a mild headache typical at 7wks 6days pregnant?

Yes: Dark brown discharge and no active bleeding is very common in pregnancy. If the bleeding were to worsen or was combined with cramping, i would see your doctor asap. Headaches are super common in pregnancy due to changes your hormones. Best is to hydrate as much as possible, dehydration is #1 cause of headache in pregnancy. After that, i would try acetaminophen. Make sure your blood pressure ok.

No: This isn't typical but probably not a cause for significant concern. Early pregnancy causes significant changes in all body systems for women. The cervix bleeds very easily during pregnancy so brown discharge may be old blood that has collected in the vagina and is just now passing. Concerning signs would be bright red bleeding accompanied by rhythmic cramping.