Oh Betty I can't even imagine, but I can understand the disbelief and convincing yourself that something's wrong. I think I probably won't believe it's really happening until I'm holding a baby in my arms - and then I'll find something else to worry over.
I too have had very few symptoms - frequent urination, fatigue & 2 days where I felt crook. After last week I was convinced that my lack of symptoms meant something was wrong. I've had light cramping but that has subsided a bit. I'm sure I'll regret saying this if it happens, but I wouldn't mind a few more symptoms because I desperately want to feel pregnant!
I hope your scan is early tomorrow!