I've recently started using a Mooncup (UK Mooncup, not the silicon version of the Keeper). I'm getting used to it, but I've noticed it always sits very low in my vagina. Even if I've inserted it right the way up to my cervix it seems to work its way back down. I don't think that's right? I haven't really had much leaking, but I'm not sure it's forming a proper seal. Does this mean I'm using the wrong size, or just that I'm not inserting it properly? I use the smaller size as I haven't had a child. I always thought by vagina was quite narrow, so I'm surprised by the cup moving. Any advice would be welcome, I want to keep using my cup but if it's not sealing properly I'm not sure I trust it not to leak.