Over the past year and half - 2 years my body has just been... dumb

About a year ago I was driving and suddenly got this "cold burning" sensation on my lower back. It's like there is a small damp spot on my shirt and a cool breeze comes up. I hope that makes sense! That sensation remained for quite some time (days? weeks? I don't remember... I just know that it came back again...) I also started getting bad headaches at the base of my skull. As if there was no fluid and my brain was just heavy. My head feels so heavy too. There were times when I would wake up feeling totally fine but the moment I sat up it just knocked me back down with such incredibly discomfort. My doctor referred me to a neurologist for an MRI of my brain and things looked fine. She did say that if things got worse to come back and we'd do an MRI of the spine as well... She also explained that MS doesn't typically present in the lower back like that. I have no loss of feeling and I wouldn't describe it as "tingling". Just cold. A cold burn.
I seemed to improve (although have never returned to physical activity b/c the slightest thing would trigger my arm issues)... About 2 months ago my arm issues returned... and the past couple weeks those headaches are back (although i haven't had the awful morning ones) along with the cold sensation in the lower back.
I'm just curious if you've experienced anything similar? I'm so frustrated and depressed about my inactivity. And I just want answers - whatever those might be. I have an appointment with my GP tomorrow... but I often feel I get my best info from forums like this so I just wanted to check with you so you might share your thoughts & experiences.
Thank you so much