This is EXACTLY the same thing I do! I also recently started using nail clippers to get what I can't pick out with my fingers. I've searched all over trying to figure out why I may be doing this. Like you said, it is satisfying but it also hurts. I found that rinsing my mouth with hydrogen peroxide after I get done picking helps alot with the pain. I am 26 and I have been biting and chewing on my tongue since I was about 15. It's so annoying.
most of the time I don't even realize I'm doing it.