Haven't been on the forum for a while. At the moment I feel totally frustrated and depressed. I haven't really been able to train in the last few weeks due to a cold and a lot of stress (I am currently taking over a medical practice). In other words, my fitness is totally shot. Nothing compared to last summer, when I set my previous personal best for a 2k with 8:33.9.
My right arm is giving me problems. It has always done that here and there in the last 20 months or so since I started indoor rowing (1.6m lifetime meters). But for about half a year now, I've noticed it after almost every training session. First the problem was in my wrist, then in my elbow and now, after a 3 week break, I immediately felt it in my shoulder again. It's not a real pain. But I can tell that something is irritated. The right shoulder feels heavier than the left. I can feel the biceps tendon in particular. I also went to the physio. He said that I'm not activating the lower left trapezius properly and am therefore overloading my right arm. I've been doing exercises for this since November.
Now my question is whether it's a technical problem. I've overcome myself and recorded a video (after 30 min rowing at 20 spm, approx. 100w average, not much, I know

Can you find anything that causes the problem on the right arm (I'm right-handed)? Or general technical issues? I'd be grateful for any advice.
https://www.youtube.com/watch?v=Q5I8B1h2q1M