Hey I see you. I had some serious tennis elbow a few years ago that basically prevented me from using my dominant hand for a few weeks. I couldn't even lift a cup of water with it. I went to PT and they gave me some exercises and stretches to do. The stretches maybe helped but the exercises were trivially easy and did nothing for me. It feels like it got better just by leaving it alone more than anything. It's acted up every once in a while since then, mostly when I get cocky and do something stupid. Recently I decided to find out how to actually fix it, and I found out that the exercises they gave me were actually ineffective, according to the medical literature. In order to improve tendon health and heal chronic tendon injuries, you need to do resistance training. The best method to improve tendon strength and health is to do like 2 or 3 low rep sets, with as much weight as you can handle, every week. It takes high tension to grow tendons, with low tension doing basically nothing. You also want to do the exercises with slow deliberate motion to avoid sudden high loading of the tendons. I've been doing that for my tennis elbow for the past couple months and it has helped a lot. It was scary at first to load my elbow with a lot of weight, but I slowly worked up to it and was careful every time and haven't had a flareup since, despite doing more lifting than I have in my life. My suggestion is to find an exercise that works the problem tendons, and slowly increase the resistance over some weeks, to as much weight as you can lift. Always be slow and deliberate. It shouldn't cause you pain at any point, and if it does back off to where it doesn't.

Tldr; research says to improve tendon strength do high weight low rep exercises with slow deliberate motion. Growing tendons takes longer than muscles so take your time. Should help your pain. Is working forme.y