Used to take Lipitor but my immune system went down and I blamed ...

Used to take Lipitor but my immune system went down and I blamed the statins. Dr. at Lipids clinic changed medication from statins to ezetimibe and since using that I wake in the morning with stiff hands and arms up to the elbow. Difficulty making a fist, also have extreme lower back pain, difficult to walk or bend first thing in the morning. Also noticed bad calf muscle pain. Symptoms usually resolve after I have been up and about for about an hour. Not sure if it's the new drug but I am stopping it to see if these symptoms go away.