it sounds very similar to my issue, same spot, but mine extends up to the mid forearm I'm not sure if yours does. mine mostly spiked from barbell curls but any excessive gripping would irritate it also. since I dropped barbell curls about a month ago its felt a lot better and more tolerable. just take some time try to source out things that make it spike and cut those out. I think they said mine was fds,finger digital something maybe idk I forget. but its basically the a form of rsi... mines been an issue since January so going on 7 months now... I've heard of peoples going away after 6 or so but mines still pretty tender. I've tried a lot of myofascial stuff, pressing the area into the edge of an arm chair hurt like a b**** but it was the only thing that would help, eventuate was temporary. dry needling, I had a lot of dry needling done and it also only helped temporarily.