Is it unhealthy to have so little blood during your period that you could go a day without changing your pad? When I started on my period like 7 years ago, I used to have to change my pad every 2-3 hours. I feel healthy, and I AM healthy (I think, lol). I exercise well and eat healthy (and yes, I eat enough :)) I am 20 years old, 5 5 1/2 , and I weigh 117 lbs.