Sorry to hear you are so worried about this but are you working yourself up into an over anxious state because you fear the process or the outcome? If it is the process, is it because it was so painful as I think they are uncomfortable but certainly should not be painful. If that is the case explain to the nurse beforehand and hopefully they can help you. If it is the results or the waiting for them that is making you worry so much then tell yourself that these are procedures that we are fortunate to have available to us now days and are wise to avail ourselves of them. I tend to think if it is unpleasant I would rather get it over sooner rather than later. If you don't get it done you will worry all the more and for longer. Maybe promise yourself a little treat afterwards. Get it done and come back and tell us.