I've been using a mooncup for about 3 years. And no, it's not possible to push it up to high, although you need to be careful about where your cervix is positioned otherwise you could pinch it which would be uncomfortable. Being tense definitely doesn't help. Also, don't worry if it needs to be tilted a bit to be comfortable. So long as it doesn't leak and is comfortable for you, there are no rules about wearing a mooncup...