I had tennis elbow in both elbows at the same time -- got mine from whitewater kayaking, aggravated it with yardwork. Not a fun injury, for sure! What it took to heal it...basically wearing tennis elbow straps on both arms, every waking minute, for months (and not paddling). I'm still prone to it, and I always carry a strap in my dojo bag in case it starts acting up.
The strap pretty much were useless when I started hammering again.I still remember picking up a milk jug and dropping it from the pain!! I knew the answer but couldn't face it-I had to stop forging.
The good news is that when I did that school porject with my son, I forged up some damascus and my arm was fine. So now I am sorely tempted to go back. Even my wife is Ok with it so I think it's only a matter of time.
On a side note, who is your sensei out there in shangri la?