@lizann94
I had a bad case of mononucleosis/EBV when I was a teenager and have had a weakened immune system. I also have cervical spine issues and had ACDF surgery on c5-c6 in 2022 and having surgery on c6-c7 in a week.

My thoughts are both mono and c5-c6may be contributing to your shoulder/arm pain. If you have swollen glands, this could put extra pressure on nerves in your neck/shoulder area causing radiating pain to your arms. When you lie down, the position in your neck changes and puts more pressure on your cervical spine/spinal cord/nerve roots that causes radiculating pain in shoulders/arms.

You may need an updated MRI of your cervical spine by an orthopedic spine specialist and see a neurologist for EMG/nerve conduction studies of upper limbs. If your spinal cord is being compressed/injured, you may need treatment sooner rather than later.