So I treid squats the other day for the first time ever. Used a weight I was fairly condifent I could handle. I did three sets of ten with 30 kilos. Managed to complete all the sets comfortably and didnt feel any back strain. As soon as I finished my last rep and stepped away from the smith machine I felt my hamstring tighten up. I could barley walk down the stairs to exit the gym. Was this, in anyone's opinion, due to bad form or execution?