That looks like the hamstring area or the IT band. maybe foam roll the IT band.
It's not the hamstring, it's the IT band and maybe side of quad.
I see. I understand as well why you did that, which I hope you realized was the wrong way to tackle a pain in the quads. I had this mentality too, I always thought when ever I got pain in my muscle stretch it, massage it vigorously like you did, whatever to make pain reduced even if it meant going through painful process e.g. my back problem so I stretched it like arching backwards until I wrecked it, couldn't squat or anything for few months, hips were stretched and were wrecked. So stretching or smashing it does not always work, but massage from expert, contrast bath, ice or heat treatment. Something I still need to learn about properly.
