When I have this one tooth (behind canine/upper) worked on, I get electric shock type pain with uncontrollable twitching sensation in upper lip above and forward of that tooth. Like a nerve was being probed. Because it's so short lived, I am not concerned, but the feeling I get - a sense of dread and irritability that causes me chest pain; now that concerns me. This has happened 2x in that one tooth. No others (and I've had extensive work).

Does anyone have an explanation?

I ended up with permanent nerve damage after having dental procedures. Now I visit a website for that and am shocked how many people have had similar experiences...meaning life altering nerve pain after dental work.
I would proceed with extreme caution. Do NOT trust your dentist to inform you of this possibility. Hopefully everything is fine, but consider talking it over with an oral surgeon (just talking) and a neurologist.

Did you have symptoms while the dentist was working on it or afterwards? What did it feel like?

I didn't have symptoms at first. I actually had no pain prior to the procedure at all. My dentist had unusual and prolonged problems putting on a crown. Another dentist in the practice took over. One day, I had excruciating pain when she removed the temporary...shocking, deep, stabbing pain that is hard to describe as I was kind of in shock. My hands and body were shaking and I couldn't control the tears flowing from my eyes. She then took a three week vacation and offered no explanation for that crazy pain or plan to fix it. I went to other dental professionals for help and they just made the situation worse...I very likely got unnecessary surgeries. I'm reading a book about nerve pain and a shocking high percentage of people receive unneeded dental procedures who have nerve pain and are never sent to a neurologist. Also, there are some like me, whose dental procedures may in fact have caused the nerve pain to begin with. I visit this other website often and it sickens me how many start off with words like"after getting my tooth (pulled, filled, cleaned) etc. I ended up with permanent nerve damage and now have horrible pain in my (nose, cheek, eye, ear) etc. "several variations on a theme, many coming from dental offices and many having unneeded dental work on top of everything else costing tons of money. Sometimes the body just needs time to heal and nothing more. But after this experience, I think it's important to be aware and ask questions.