I'm not sure what you mean by a vegal reaction, and found nothing by searching.
You may need to review medications and anything else that you take to see if the cause is there.
It may be unrelated to the DDD.
It may be more to do with stress.
I have similar spinal DD and I take mainly pain meds to handle it, with an occasional Celebrex anti-inflammatory, plus gabapentin.
They all help with the bone type of pain, and a bit with the muscle pain, but by far the best treatment I've found for muscular pain is magnesium chloride.
It is also called magnesium oil, and is just mineral rich deep-sea water.
You rub it onto the skin several times a day, ideally on the sore muscles, but anywhere is good.
Personally, I found that a bit of a nuisance so I now drink 1 teaspoonful in a large drink bottle of water, sipping throughout the day.
The results have been amazing, stopping all of my muscle pain in 2 weeks.
Have a read about it online, and you may then like to try it.
It is the best thing I have found, better than remedial massage too as it works permanently.
Once you have the muscles back to normal, you can then try exercises again.
I have been told that it is important to keep active, other wise the spine gradually seizes up, restricting movements and activity.
I use Echolife magnesium oil.
You can also get powders and tablets, but the oil is far more effective and faster.
Take a good multi vitamin as well as you need to have calcium for the oil to work well.