iterative process of injury followed by determining how to avoid pain and continue your constructive weightlifting routine. You have a good amount of experience at this already. Good luck. I've always found furniture and dogs destructive and can avoid one of the two.
I don't have a bulge or rupture just some lumbar arthritis but something is pressing on the sciatic nerve, possibly piraformis muscle. Physical therapy has helped, also had acupuncture but can't comment on the effect...didn't hurt.
I screwed mine back in the real work days. Mine was definitely muscular, according to the doctor, and I'm pretty sure he was correct. After that 2 to 3 times a year it would go out. Most of the time I knew when it was going to happen and no matter how careful I was it would happen. For me I took Aleve and would lie flat on our hardwood floors allowing the muscles to relax. Getting up was an intentionally slow process of rolling gradually to my side and working up from there. This and for the most part avoiding any activity had me back in usually 3-4 days. After about 5 to 8 years of this I finally got a clue and started working hard on my core. I also bought an inversion table and still use it. I haven't had an issue in quite a few years now other than I discovered that leg raises are a no go for core work as the next day I have that feeling my back is about to go out. You obviously have a solid core, and like Des mentioned the electric shock feeling would have me thinking the sciatic nerve. Our oldest has sciatic nerve issues as a result of a football injury. He's found massage a help when it starts giving him a problem. If I recall its the deep tissue kind of massage he gets from the person.
The only experience I have with this type of pain is a sudden pulled-muscle in the lower back which drops me to the floor and leaves me there for 5 or so minutes. I have never had an electric-shock feeling with back pain though.
Oh hell Yeah! 20+ years ago, would ride my bike to college, took Tae Kwon Do. I think we were working on jump spinning back kicks where one is standing in a fighting stance and in one motion jump up to face the opposite direction and the rear foot extends out in a back kicking motion. A fun exciting kick, knocked a guy out with it once, it requires lots of "core" stuff being activated. I recall massive spasms, layed on the ground curled up for a long time, had to call for a ride home. Took a while to recover, many days. Other smaller issues along the way, generally with heavy stuff. For acute issues like this, REST is the best idea. One could get narcotics and muscle relaxants and then be comfortable, but perhaps the pain from injury is really telling you to sit down, don't re injure. Norton Hadler MD talks about how screwed up we are with regards to back health in his book Worried Sick. Hint: life is about living with some pain! Trader Don Miller talked about his back issues on a blog post and I agree that a massage is one of the worst things one can do for upper back and neck pain: http://donmillerblog.com/2011/07/01/ I had intense neck and arm pain and had to give up on massage as it made it worse. Chiropractic saved me from 30+ years of pain from high school. I use a denneroll for my neck roll my entire back on a hard foam roller, and also lay on a lumbar extender positioned up and down my back. My back and neck pain was made worse by trying to get my 10,000 hours of screen time in as a trader.
I'm feeling back on track today and I'm grateful for that. I was able to get into the gym this morning and do some hyperextensions and ab work to tighten up my core. From this point forward, I'm going to do core work three times per week because it seems like every time I slack on that, I end up with this same recurring back issue. I will admit that I've been lazy with the core work lately, and I paid the price for that laziness the last few days for sure.