This typically stems from incorrect wrist position, and, unfortunately, once you have a tendonitis problem, even the slightest insult can make it flare up. I caught a glimpse of your wrists in the video and noticed some flexion on the left hand. Is it possible that you used to squat with bent wrists and are now overcompensating? Regardless, two things will help: perfectly straight wrists, and an aggressive ibuprofen regimen. If I were in your shoes, I might do 800mg 4x/day for 5 days, but I'm not a doctor and have no business giving out medical advice.