Good question. It's actually ironic because as I said it was after I had dropped the weight from the heavier sets so I think it was more just a lack of focus on my form after that. Having said that I had certainly lifted my training of legs the past 4-6 weeks from doing it very rarely to doing legs twice a week so whether this contributed to it as well, i'm not sure.Out of curiosity, why do you think the injury happened? Too much weight? Not enough warm-up?
FWIW the pain is still there so I actually went to the doctor yesterday afternoon after going to the physio on Friday. I've actually popped a rib so that explains why this hurt a bit more than a pulled muscle last time and also explains why it's still lingering