nexplanon

Ariesdyce
Hey so I got the nexplanon put in June 12! My period was suppose to come on the 10 & it never did! Then it finally came on the 22 but it was brown blood like old blood that never came out now it's regular blood. My period is usually like 7 days! Will it be longer or the same? Is my body just adjusting to the birth control? Can anybody help me?