My moms back is in extreme pain, i think its muscle pain. she is lying down and can't really move. she just sneezed and she started yelling in pain.

You are right: If it doesn't improve, she needs to see her doctor to evaluate whether it's back pain, or possible bulging or herniated discs. Her PCP can advise whether imaging is needed, as pain meds alone will not be enough if she can't move or get out of bed. She can use NSAIDS short term only, but evaluation is key so that she can be treated and not be deconditioned. She may need to see a spine specialist!