Howdy BOO, I was in the dentist's chair at 8:20 this morning and I can confirm that today is the ideal day for a check-up. A quick look around, scale and polish and presto magico, that'll be £10.20 please and we'll see you in 6 months.
I used to be an armrest gripper after a very bad experience as a child and I know you don't like the oft repeated "modern dentistry is painless" line but the reason it's oft repeated is, it's true.
I'm sure your dentist didn't study all those years to learn how to inflict pain, anybody could do that. As others have said have a chat, have a valium (nice drug) and try to recall what the experience with the abcess was like. You know deep down that a visit to a health professional can't be worse than that!
Come on, join the happy smile club. Good luck! :D