So according my my lmp, I'm 11 weeks 5 days pregnant

Anyways I have this weird goosebumps looking things on my belly and headed to google, it took me to an article about symptoms and mentioned about a weird period could be a sign of pregnancy. I put that down to run up to the wedding and stress etc. On a whim I checked out my lmp before that and worked out I would be 17 weeks - can you imagine?!? Would explain why I'm already showing and could feel the baby (well vibrations and flutters) so strange - anyway scan on Friday, time will tell