Yeah. Like everyone says. there's more than one possible condition. How would we, a bunch of dudes and dudettes ona forum know.
I probably know more than he average person, but there's no guarantee and I would still have to see YOUR arm.
Yes. Not all doctors are the best these days. The nature of the profession is that of people ag gas stations and garages selling bread and ice cream and knowing nothing about cars anynre. Just the way it is. But hey. That's why you shold get a second and third opinion from those you feel most inclined to trust.
Just to blabber on a bit.
Good technique is what? How do we know? That's also personal and it all goes out the window if we're tired and practice too much. Especially if we're practicing one thing and one movement.
No matter how good it is, repetitive stress injury will happen if not propper care and precations is taken. Breaks, full movement, stretching, propper nutrition, hydration and rest. There are a number of ways to treat and there are a number of ways to prevent. Some are general and should just be part of one's routine, some may be particular to a condition that you now might have which brings us, in this case, back to what most others have said.
Age definetly matters. I'm maybe young to some, but at 40 it's not like I was 20. Practicing and working out the same is no problem, but diet is a whole different matter.