I've Been Experiencing Stiffness In My Lower Back And Buttocks

I've been experiencing stiffness in my lower back and buttocks after I'm in bed sleeping for about 4 hours.

When get out of bed it feels like I have a sprained lower back. It's painful and difficult to bend over without supporting my upper body but here is where it gets interesting. Once I'm up for anywhere from 10 minutes or so the pain and sprained feeling goes away. I can carry on about my day doing anything I desire without any pain/discomfort or feeling that my back is sprained. In the middle of the night I typically have to get out of bed and stretch out my hamstrings and gluts.....it seems like the muscles shrink after a few hours in bed. I have tender spots in my buttocks, hips and lower back so I try to use the rolled on a daily basis to try and work out those spots but it just doesn't get any better. I've been like this for 2 years now.

I've been seeking a wide range of treatments from Chiropractic, massage, acupuncture, prolo therapy, I MS and it has yet you go away.

Last night while laying in bed I was massaging the area and felt what feels like localized swelling in my right buttock. Feels like some sort of mass.

Any advice would be greatly appreciated