I didn't want you to feel as if implied that you definitely DO have any of these disorders. I am simply stating that these are some of the disorders that cause pain especially in the lower extremities as you mentioned.
I am very new to this forum, I love health topics and suffer with many health issues myself.
I do a lot of research for friends and family, and have a wealth of knowledge. I realize I need to be more careful about using the proper terms in discussing these topics in this forum. I have a strong desire to assist others as well as to help alleviate suffering. When you are confused by symptoms it is great to know there are answers out there.
I hope that you might ask your Dr. for a full spinal evaluation along with x-rays, cat scans and MRIs, Take a list of questions so as to ask him about all the different spinal problems, such a sciatica and degenerative disc disease. These are very painful, and I hope you can obtain the correct diagnosis, along with peace of mind and ultimately feel better.
NOTE: I have used Chiropractic care as well as massage therapy and acupuncture successfully for my back pain, and I know of many others who have also explored these options with very good results. I feel it might be good idea to ask your Dr. if either of these might be suitable options for you.