Please help Im haveing mini freak out type things about death when im about to fall asleep?

When im all snuggled up in bed hugging my buzzlightyear doll about to doze off then i have this mini freak out type thing, it happens almost every night, i start thanking about reincarnation and then i start freaking out because what if life's just some thing that we repeat over and over and over again and that this life means nothing and im just going to forget everything and start over as someone else and it's just going to keep happening and i have no control over it. how can i make these thoughts stop? because i don't want them TT^TT