To be honest, I find cleanings (deep or otherwise) to be pretty easy, I normally opt to not have any numbing for this as I don't find the process uncomfortable but that will obviously depend upon the individual.As far as a filling is concerned, once you are numbed up you should find it a little strange but painless, the best thing to do is to tell your dentist what you do or don't like and (s)he will usually try to accompdate you and go at your pace. On the subject of local anaesthetic injections, it depends upon the dentist but I've found that I barely feel these being done, my dentist is so good at these that on a scale of 0 to 10, the most I've ever experienced would be a 1.
I will be joining you tomorrow as I have part 2 of a root canal then; strangely enough I'm totally calm as the first phase was so easy. It makes all the difference having a great dentist that you trust. Good luck, I'm sure you will fine and I will see you tomorrow on " the other side" ?