bruises on my shoulder

50 mins strength training
20 mins treadmill, 6.3

I blew through my strength training workout today, probably because I skipped the warm-up (which is bad). However, I did cycle to the gym so that counts as warm-up. I somehow got bruises on my shoulder, which I think are from the dumbbells I used when doing power squat shoulder presses. Running felt good today too - I think the orthotics make a difference for my body alignment.