I have spine issues too, and while I can't do exercise in the truest sense of the word, I do have to do stretches and the like. Each of us with this type of problem has to find what types of exercising we can do. It's imperative that we keep our muscles toned, or they act up and make our initial problem worse. (Think: more pain.)

I must do physical therapy, but it isn't to exercise, it's to be stretched out because I'm not strong enough to maintain full function of my muscles by myself. I can not lift anything over 3 lbs without consequences, but I do flex my muscles and work them when I pick up those 3lb items. I cannot walk ,but walking is a great exercise for maintaining most muscles.

I think you overdid in the gym. Keep going, but cut back on what or try new things instead. Keep track of what you can get "away" with doing without any more effect than perhaps fatigue. We all have to push ourselves, otherwise, the pain would prevent us from doing anything.

((((gentle hug)))