I was very surprised to read that you have pin pricks( it is also called paresthesia) from a muscle relaxer. Have you taken muscle relaxers for any period of time? I am not trying to throw a wrench here and I am not a Dr. but I have had pin pricks. I have an odd story. I woke up one morning and I had full onset everywhere of pinpricks including my eyes. I asked my neurologist how many of his patients had what I did and he said none it is rare. But here is my question do you know if you have stenosis in your back? Stenosis is a narrowing (an hour glass has a narrowing in the center of it) So I do know that with stenosis you can have pin pricks also. You also said you hurt your back at the gym. I looked up muscle relaxers and I couldn't find anything about pin pricks. Have you had an MRI with contrast because that would show things if you have it. I know you need answers. Believe me I know how it feels. I went to a neurologist and they did a bunch of tests-bloodwork, genetic testing and finally a skin biopsy. It showed I have small nerve fiber that is idiopathic meaning no known cause. It really is nerve racking when you need answers and I fully understand that. I have severe stenosis in my neck one area is both sides and one is one side in the disc. I have a brother who had (sciatica-which is pain) down both legs. He had a herniated disc. He had surgery for that. I certainly cannot diagnose you but seeing a neurologist should help you find out what is wrong. I also think an MRI with contrast should give them a picture of things. I do read things but I am interested in knowledge about my issues. I am a retired nurse so I do understand most medical words. Some I have to look up some because I never heard of it. I do know that as we age and I admit I just turned 68 okay that if you took a random set of people off the street and did MRI's on them you would find back degeneration. That is called aging. It is hard when you have to wait to see someone. Been there done that. Here is one thing that I like to do. Take a note pad and write down what happened to you. Don't write a book. Keep it short and sweet. Then write down your questions that you want to ask the Dr. I do that because if I don't I might get home and the one thing I really wanted to ask I forgot. Of course you need answers. The doctor will ask questions but I think some notes and questions would be good for you to write down. I wish you the best of luck when you see the Dr. and hope you find answers. I am still looking for some. I have an appt to see a neurosurgeon in November but I am trying not to get hopes up that he will be able to solve my issue. The most important thing is you are going to the Dr. to find out. Be prepared it really helps.