I wouldn't say your a time waster as long as you tell them you cant make it then thats fine time wasters we feel are people that say that want to meet then never show up don't call or text to let us know.
I wouldn't worry to much when I was a single fem on here it took me ages till I would meet for a shag I would meet in café first for a chat that way if I didn't get a good feeling I would just go home on my own.
A timewaster is someone who wastes another's time regardless of the reason.
But if that prospective timewaster is up-front right at the beginning that a cancellation due to nerves or whatever is a possibility then that person is not a timewaster. They were honest enough with the person to warn them thereby giving the other person a choice on how to proceed.
Which category the OP is in is up to the OP to decide for themselves. They don't really need us to answer it for them. They probably already know and just need confirmation.
I only regard a timewaster as someone who causes someone else wait for them and never shows up. If someone calls off a meet up to a few hours beforehand, whatever reason they give, I don't regard them as having wasting my time.