Good luck with your appointment, litch123. I am doing exactly the same, going from thinking positively to thinking the worst. Some people have the attitude of "it will never happen to me" and I really envy them for it! I end up thinking the opposite, that if it is going to happen then it could quite easily happen to me.
I have recently banned myself from reading any of those stories where someone was misdiagnosed and now has 3 months left to live, because they do nothing but stir up anxiety and get people talking about how their neighbour's best friend's cousin also had the same cancer and died. Sometimes it feels like the only purpose of those articles is to get anxious people to click on them!
Fingers crossed that by the end of the week everyone here has good news (I'm sure we will!).