Low back pain first thing in the morning is very common. Unfortunately there are many contributing factors that cause low back stiffness first thing in the morning. The underlying cause is usually low back arthritis or an existing injury to a lumbar disc. However, there are many aggravating factors that can contribute to the morning low back pain and stiffness. These include but are not limited to the mattress, you sleep position and finally the way you sit up out of bed.
This last maneuver is similar to a sit-up which puts a ton of strain and compression through the lumbar spine,.
This is made even worse by the fact that your discs re-hydrate overnight and increase your risk of low back injuries with certain movements.
Below is a video explanation of a better way to get out of bed, or off the couch when you are laying on your back.