12 week scan....what if I've imagined it!

Hi! I'm freaking out! I've got my 12 week scan tomorrow so I'm gonna see my baby for the first time and I'm so scared! When I first tested I did about 10 tests as I kept testing until I got a pregnant 3+ weeks on a clear blue digital because it just wouldn't sink in! I've been waiting for over 8 weeks for this but I'm terrified something will be wrong or that there will just be nothing there and it will turn out that I'm a crazy lady who has imagined these last 2 months!