I Have Chronic Pain In My Upper Right Arm That

I have chronic pain in my upper right arm that varies in intensity. About 5-6 years ago I underwent physical therapy for very similar pain, caused by repetitive use (throwing hay overhand); the therapy helped and I was pain-free for several years. The pain started again, intermittently, about a year ago (I don't throw hay anymore), and has become constant. Many nights I wake up to a very achy arm and have difficulty moving it. It also 'catches' me sometimes when I move it to perform simple tasks, like reaching up to a lamp, reaching for my purse next to me, etc. Ibuprofen helps a little. I'm female, age 57, overweight, control my blood pressure with 10mg/daily of Lisinopril, but otherwise healthy with good bloodwork. I take 2,000 cc of Vitamin C and 5,000 IU of Vitamin D3 daily. I don't smoke or take drugs, and only drink lightly, socially. I also have occasional stiffness and aches in my ankles and lower back. Help?