Why when I'm laying or sitting down in my period underwear which is the only thing I use the blood goes everywhere

Okay so this totally happens, and it's super annoying when your period underwear doesn't feel like it's doing its job. It's usually because period underwear has a super absorbent pad built in, but that pad might not go all the way up the back or front when you're sitting or lying down.

Gravity is literally doing its thing, and if your flow is a little heavier, the blood just moves to the parts of the fabric that aren't absorbent. It's not a leak because the underwear is broken or anything, it's just that the protective part doesn't cover all the angles you're in. Your body position can really change where the blood goes!

To help with this, you could try a different brand or style of period underwear that has more coverage, especially in the back. Some are designed more for sleeping or heavy flow and have a bigger absorbent area. You can also try wearing a pad (even a thin one) as backup, especially on heavier days or if you know you'll be lounging around a lot. And if you're worried about your flow being super heavy, it's always good to chat with a grown-up about it, just to make sure everything's okay.