Thank You And Hello, My Name Is Dr, Michael Miceli

Thank you and Hello, my name is Dr, Michael Miceli and I am an Archaeologist in field work. I have developed a coed like raised area in the palm of my hand. It is slightly painful but whatever is happening is either the result of or start of pain radiating up to my elbow and into my shoulder. Now I can feel soreness in my upper chest area in my muscle...so, I know I need help, but I think this is way past the so-called tennis elbow....

I have looked on line and hope I don't have rotator cuff injury...well, could you identify the lump in my hand? I also hand rheumatoid arthritis but I work past it the best I can.....thank you so much in advance....oh, and I am female, aged 65 ...