Lower Back Pain

Help! Whenever I do a lower body strength routing, it seriously hurts my mid to lower back. I've been working out and doing strength training for 5 years now. When I used to do classes like these at a gym, I didn't notice it that much, but whenever I do it myself at home, it seriously makes my lower back sore! I'm not sure if I'm just lifting too much and compensating by using my back too much or if it not too much weight and my form isn't great. Any advice??

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