I know EXACTLY how you feel, OP. When I got my eyes tested for the first time I was certain they'd find something. In fact, it took over five years for me to get my eyes tested after they started going bad!
I had it all done - it was kind of odd, and there's this part where they puff a bit of air on your eye which was unpleasant, but all I was told was that I was short sighted and that my glasses would be ready within two weeks. Nothing bad, nothing weird, and since then I haven't worried about tumours. I am sure you will be fine. Actually I am way overdue my next eye test...let us know how you get along. :)