My lower back is hurting on my right side making me very restless. along with my neck and right shoulder. what could this be?

Muscle pain: This could be a simple as muscle spasm. Muscle spasms can come from stress, or muscle strain from lifting heavy things or strenuous activity. Something that might relieve the pain of muscle strain or spasm are warm compresses, Epsom salt soaking baths, home stretching exercises, massage therapy, and over-the-counter pain relivers. However, if this pain does not resolve on its own, see your doctor.