Excersise

[Makachop^^128]

This is more asking advice then anything, anyway, I've always been somewhat skinny, but recently the few past months I've gone to having a 23" waist to having a 26" waist, I've been exercising, I walk about 3 miles a day and do other exercises at home, and the past few months I've been eating better, so I have no idea why I've been getting bigger :/ Do Women still grow at 17-18 years old? could I be growing?