I am praying with you for the pain in your right shoulder and for the freedom and relief you are asking God to bring. It is hard when you hurt and you do not know the cause, and I want you to know that God sees you and cares about this need.
Scripture helps us understand suffering in a fallen world. Not every sickness or pain is a direct result of something you have done. Good people do experience illness and pain, and that does not mean God is punishing you. In a perfect world there would be no pain, but because sin entered the world, our bodies are subject to weakness and hurt. All of these things come indirectly from living in a broken creation, and God has compassion on us in it.
The Bible also shows that Jesus healed in different ways. Sometimes He healed with only a word, sometimes with a touch, and sometimes there was a point of contact where a person's faith was released to receive what He was already willing to give, like the woman who touched the hem of His garment and power went out from Him to heal her. However He chooses to work, He is the same Lord who heals today, and we can bring your shoulder to Him in simple trust and ask Him to touch it and restore it.
There is also a beautiful picture in Scripture connected to the right side of the body. Under the old covenant, when priests were set apart for service, blood was placed on the tip of the right ear, on the thumb of the right hand, and on the big toe of the right foot, and the right shoulder of the ram of consecration was offered to God. It was a picture of a life set apart, an ear consecrated to hear God's voice, a hand consecrated to do God's work, a foot consecrated to walk in God's ways, and strength consecrated to serve Him. Your right shoulder in that picture speaks of strength and service. My prayer is not only that God would take away the pain, but that He would touch that shoulder and consecrate your strength to Him, so that whatever healing He brings will be for His glory and for your joy in serving Him.
True freedom is also more than just relief from pain. It is the freedom that comes from abiding in Jesus, being freed from sin and walking in fellowship with Him. Jesus spoke of the fullness of joy that comes from abiding in Him, and that joy and freedom remain even while we wait for answers to prayer.
So I am asking the Lord to lay His hand upon your right shoulder, to ease the hurt, to reveal and remove the cause if it is His will to show it, and to bring complete healing according to His wisdom and love. I am asking Him to give you peace while you wait, to guard your heart from fear, and to use even this trial to draw you closer to Him. May He strengthen you, comfort you, and let you know His presence in a very real way, and may your life, including your strength, be set apart for Him.